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Ataxia-Telangiectasia 
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Ataxia-telangiectasia results from a DNA repair defect that frequently results in humoral and cellular deficiency; it causes progressive cerebellar ataxia, oculocutaneous telangiectasias, and recurrent sinopulmonary infections.

Inheritance is autosomal-recessive. Estimated incidence is 1 in 20,000 to 100,000 births. Ataxia-telangiectasia is caused by mutations in the gene that encodes ataxia-telangiectasia–mutated (ATM) protein. ATM is involved in detection of DNA damage and helps control the rate of cell growth and division. Patients often lack IgA and IgE and have a progressive T-cell defect.

Symptoms and Signs
Age at onset of neurologic symptoms and evidence of immunodeficiency vary.

Ataxia is frequently the first symptom and usually develops when children begin to walk. Progression of neurologic symptoms leads to severe disability. Speech becomes slurred, choreoathetoid movements and nystagmus develop, and muscle weakness usually progresses to muscle atrophy.

Telangiectasias are widely open (dilated) blood vessels.

Telangiectasias may not appear until age 4 to 6 yr; they are most prominent on the bulbar conjunctivae, ears, antecubital and popliteal fossae, and sides of the neck.

Recurrent sinopulmonary infections lead to recurrent pneumonia, bronchiectasis, and chronic restrictive pulmonary disease.

Certain endocrine abnormalities (eg, gonadal dysgenesis, testicular atrophy, diabetes mellitus) may occur.

Frequency of cancer (especially leukemia, lymphoma, brain tumors, and gastric cancer) is high. Cancer typically occurs after age 10 and at a rate of about 1%/yr but is a lifelong risk and can occur at any age.

Diagnosis
• IgA and serum α1-fetoprotein levels
• Genetic testing

Clinical findings of cerebellar ataxia (particularly when telangiectasias are present), low levels of IgA (present in 80% of patients with this disorder), and high levels of serum α1-fetoprotein suggest the diagnosis. If karyotype analysis is done, chromosome breaks, consistent with a defect in DNA repair, are often seen. Diagnosis is confirmed by identifying mutations on both alleles of the gene for ATM protein. Because carriers of an AT mutation usually remain asymptomatic, testing siblings for a carrier state can help predict their chance of having an affected child.

Testing for endocrine abnormalities and cancers is done based on clinical presentation.

Treatment
Supportive care using prophylactic antibiotics or IV immune globulin
Treatment with prophylactic antibiotics or IV immune globulin may help. In one small study, treatment with amantadine resulted in minimal improvement in motor function, but there is no effective treatment for the progressive neurologic deterioration, which causes death, usually by age 30.

Chemotherapy is often indicated for treatment of associated cancers.

CLINICAL VIGNETTES

A 4-year-old girl is brought to the office by her mother because of skin lesions on the face and arms. She recently noticed them, first on the eyeballs and then on the cheeks and in the elbow crease in increasing numbers. They do not appear to bother the patient. The child's medical history is significant for a gait disorder that began when she started to walk and progressively worsened, and for recurrent sinopulmonary and skin infections. She now has an awkward, swaying gait with choreic and athetoid movements. On examination, there are multiple nonblanching, dilated blood vessels present on the bulbar conjunctivas, on the nose and cheeks, and in the antecubital fossae. The child is drooling and has erythematous, scaly patches with thick purulent crusts on the comers of the mouth. Which or the following is the most likely diagnosis?

A. Ataxia-telangiectasia
B. Chronic granulomatous disease 
C. IgA deficiency
D. Sex-linked agammaglobulinemia
E. Thymic hypoplasia

The correct answer is A . This patient has ataxia-telangiectasia, a syndrome that consists of ataxia, telangiectasia of the eyes and skin, chronic sinopulmonary disease, and endocrine abnormalities. The syndrome is transmitted as an autosomal recessive trait with a defect in the ATM gene located at chromosome 11q22-23. The defective gene codes for a protein kinase. Cerebellar ataxia is the first neurologic sign that most commonly manifests as the patient starts walking. An awkward swaying gait develops, followed by choreic and athetoid movements that worsen with time. Commonly, there are recurrent sinopulmonary infections, impetigo (erythematous, scaly patches with thick purulent crusts), herpetic gingivostomatitis, and lipoatrophy. On physical examination, the patient has a masklike facies with drooling, abnormal eye movements and tics. lgA, lgE, and lgM levels are low. CD3+ and CD4+ T cells are moderately reduced, with moderate or increased numbers of CDS+ T cells. Both the T and B cells are defective. Persistently elevated levels of alpha-fetoprotein and carcinoembryonic antigen occur and may help in early diagnosis of disease. Children are usually confined to a wheelchair by the age of 12. Severe pulmonary infections and bronchiectases complicate the clinical course. Lymphoid malignancies develop in approximately 30% of patients and are the most common cause of death.

A 4-year-old child is evaluated by a neurologist because of difficulty walking. Neurological examination documents ataxia and mental retardation. The neurologist notes the presence of multiple telangiectasias involving the conjunctiva, ears, and antecubital fossae. The child also has a history of multiple respiratory tract infections. Immunoglobulin studies on the child would most likely demonstrate an absence of which of the following?

A. IgA and IgE 
B. IgA and IgG 
C. IgE and IgG 
D. IgE and IgM 
E. IgM and IgG 

A. The child's condition is the autosomal recessive disease, ataxia-telangiectasia, which is a multisystem disorder of unknown etiology. The ataxia is noticed in early childhood, and with time, progresses to severe disability. Choreoathetoid movements, slurred speech, ophthalmoplegia, and progressive mental retardation characterize the disease at it advances. Telangiectasias, as described in the question stem, are a helpful diagnostic clue. These children also are vulnerable recurrent sinopulmonary infections. Immunologic evaluation may demonstrate a lack of IgA and IgE, cutaneous anergy, and a progressive cellular immune defect. Other features of the syndrome include endocrine disorders and a predisposition for certain cancers (leukemias, brain cancer, and gastric cancer). Most of these patients die of their neurologic deterioration by age 30. 

IgG (choices B, C, and E) and IgM (choices D and E) are not specifically affected in this condition. 
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Patent Ductus Arteriosus 
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Patent ductus arteriosus (PDA) is a persistence of the fetal connection (ductus arteriosus) between the aorta and pulmonary artery after birth, resulting in a left-to-right shunt. Symptoms may include failure to thrive, poor feeding, tachycardia, and tachypnea. A continuous murmur at the upper left sternal border is common. Diagnosis is by echocardiography. Administration of indomethacin with or without fluid restriction may be tried in premature infants with a significant shunt, but this therapy is not effective in term infants or older children with PDA. If the connection persists, surgical or catheter-based correction is indicated.

PDA accounts for 5 to 10% of congenital heart anomalies; the male:female ratio is 1:3. PDA is very common among premature infants (present in about 45% with birth weight < 1750 g and in about 80% with birth weight < 1200 g).

Pathophysiology
The ductus arteriosus is a normal connection between the pulmonary artery and aorta; it is necessary for proper fetal circulation. At birth, the rise in Pao2 and decline in prostaglandin concentration cause closure of the ductus arteriosus, typically beginning within the first 10 to 15 h of life. If this normal process does not occur, PDA results.

Physiologic consequences depend on ductal size. A small ductus rarely causes symptoms. A large ductus causes a large left-to-right shunt. Over time, a large shunt results in left heart enlargement, pulmonary artery hypertension, and elevated pulmonary vascular resistance, ultimately leading to Eisenmenger syndrome.

Symptoms and Signs
Clinical presentation depends on PDA size and gestational age at delivery. Infants and children with a small PDA are generally asymptomatic; infants with a large PDA present with signs of HF (eg, failure to thrive, poor feeding, tachypnea, dyspnea with feeding, tachycardia). Premature infants may present with respiratory distress, apnea, worsening mechanical ventilation requirements, or other serious complications (eg, necrotizing enterocolitis). Signs of HF occur earlier in premature infants than in full-term infants and may be more severe. A large ductal shunt in a premature infant often is a major contributor to the severity of the lung disease of prematurity.

Most children with a small PDA have normal heart sounds and peripheral pulses. A grade 1 to 3/6 continuous murmur is heard best in the upper left sternal border. The murmur extends from systole to beyond the 2nd heart sound (S2) into diastole and typically has a different pitch in systole and diastole.

Full-term infants with a significant PDA shunt have full or bounding peripheral pulses with a wide pulse pressure. A grade 1 to 4/6 continuous murmur is characteristic. If the murmur is loud, it has a “machinery-sounding” quality. An apical diastolic rumble (due to high flow across the mitral valve) or gallop rhythm may be audible if there is a large left-to-right shunt or HF develops.

Premature infants with a significant shunt have bounding pulses and a hyperdynamic precordium. A heart murmur occurs in the pulmonary area; the murmur may be continuous, systolic with a short diastolic component, or only systolic, depending on the pulmonary artery pressure. Some infants have no audible heart murmur.

Diagnosis
Chest x-ray and ECG
Echocardiography
Diagnosis is suggested by clinical examination, supported by chest x-ray and ECG, and established by 2-dimensional echocardiography with color flow and Doppler studies.

Chest x-ray and ECG are typically normal if the PDA is small. If the shunt is significant, chest x-ray shows prominence of the left atrium, left ventricle, and ascending aorta and increased pulmonary vascular markings; ECG may show left ventricular hypertrophy. Cardiac catheterization is not necessary unless used for therapy.

Treatment
• Prostaglandin synthesis inhibitor therapy (eg, indomethacin, ibuprofen)
• Sometimes transcatheter occlusion devices or surgical repair
In premature infants with compromised respiratory status, the PDA can sometimes be closed by using a prostaglandin synthesis inhibitor (eg, indomethacin. Three doses of indomethacin are given IV q 12 to 24 h based on urine output; doses are withheld if urine output is < 0.6 mL/kg/h. An alternative is ibuprofen 10 mg/kg po followed by 2 doses of 5 mg/kg at 24-h intervals). Fluid restriction may facilitate ductal closure. In the past, if this treatment was unsuccessful, the PDA was ligated surgically. However, current data do not show improved long-term outcome after surgical intervention, but experts are evaluating whether there are subgroups of patients in whom surgery might be beneficial. In premature infants without respiratory compromise, a PDA is generally not treated.

In full-term infants,indomethacin is usually ineffective. Transcatheter closure has become the treatment of choice in children > 1 yr; a variety of catheter-delivered occlusion devices are available. In infants < 1 yr or who have certain anatomic varieties of the ductus, surgical division and ligation may be preferred over the transcatheter approach. For a PDA with a shunt large enough to cause symptoms of HF or pulmonary hypertension, closure should be done after medical stabilization. For a persistent PDA without HF or pulmonary hypertension, closure can be done electively any time after 1 yr. Outcomes after PDA closure are excellent.

Key Points
• Patent ductus arteriosus (PDA) is a persistence after birth of the normal fetal connection (ductusarteriosus) between the aorta and pulmonary artery, resulting in a left-to-right shunt.
• Manifestations depend on the size of the PDA and the degree of prematurity, but a continuous murmur is characteristic and, if loud, has a “machinery-sounding” quality.
Premature infants may have respiratory distress or other serious complications (eg, necrotizing enterocolitis).
• Over time, a large shunt causes left heart enlargement, pulmonary artery hypertension, and elevated pulmonary vascular resistance, ultimately leading to Eisenmenger syndrome.
• Give premature infants a prostaglandin inhibitor (eg, indomethacin) to close the PDA; surgical closure has not been shown to improve outcomes.
• Prostaglandin inhibitors are usually ineffective in full-term infants, but catheter-delivered occlusion devices or surgery is typically beneficial.

CLINICAL VIGNETTES

A pediatrician examines a 2-month-old infant who had been born at term. The pediatrician hears a continuous murmur at the upper left sternal border. The peripheral pulses in all extremities are full and show widened pulse pressure. Which of the following is the most likely diagnosis?

A. Coarctation of the aorta 
B. Patent ductus arteriosus 
C. Peripheral pulmonic stenosis 
D. Persistent truncus arteriosus 
E. Ventricular septal defect 

B. This is patent ductus arteriosus, which is a failure of closure of the duct between the pulmonary artery and the aorta. As many as 80% of significantly premature (<28 week gestation) infants have patent ductus arteriosus. In term infants, delayed closure is diagnosed if the murmur of the patent ductus (described in the question stem) is still present at 6-8 weeks of age. Infants should be evaluated for other cardiac disease, since a patent ductus arteriosus may be partially compensating for other cardiac anomalies. Infants with heart failure require prompt surgical correction. Infants without heart failure or complicating cardiac defects typically undergo elective surgery at 6 months to 3 years to reduce the risk of infective endarteritis later involving the patent ductus. 

Coarctation of the aorta (choice A) will cause diminished pulses in the legs and sometimes arms. 

Peripheral pulmonic stenosis (choice C) causes murmurs heard over the lung fields. 

Persistent truncus arteriosus (choice D) is a failure of the aorta to separate from the pulmonary artery, and causes heart failure within days to weeks of birth. 

Ventricular septal defect (choice E) causes a murmur heard best at the lower left sternal border. 

During cardiac examination of a newborn infant, a murmur is detected, and the diagnosis of patent ductus arteriosus is made. Which of the following best describes the direction of blood flow through the patent ductus arteriosus in this infant?

A. From aorta to left pulmonary artery
B. From aorta to left pulmonary vein
C. From aorta to right pulmonary artery
D. From left pulmonary artery to aorta
E. From right pulmonary artery to aorta

The correct answer is A. The ductus arteriosus connects the left pulmonary artery to the aortic arch. It is derived from the left sixth aortic arch. During prenatal life, the pressure gradient causes blood to flow from the left pulmonary artery to the aorta. However, after birth, the pressure gradient reverses, and if the ductus arteriosus remains patent, the flow is from the aorta to the left pulmonary artery.

The ductus arteriosus does not connect to the pulmonary veins or the right pulmonary artery (choices B, C, and E).

The flow through the ductus arteriosus is from the left pulmonary artery to the aorta (choice D) prior to birth, but reverses after birth.

Patency of the ductus arteriosus can be artificially prolonged after birth by administration of

A. glucocorticoids
B. indomethacin
C. insulin
D. oxytocin
E. prostaglandins

The correct answer is E. The ductus arteriosus is an arterial channel connecting the aorta with the pulmonary trunk during intrauterine life. Closure of this embryonal vessel occurs in the first few days after birth. Patency of the ductus is maintained by prostaglandins, more specifically prostaglandin E. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as indomethacin (choice B), promote closure of this structure since NSAIDs inhibit prostaglandin synthesis. Prostaglandin E and NSAIDs can be used therapeutically to maintain a patent ductus arteriosus or to promote its closure. 

Glucocorticoids (choice A) can accelerate pulmonary maturation and stimulate production of surfactant, but do not affect the ductus arteriosus.

Insulin (choice C) inhibits surfactant production, but has no effect on the ductus arteriosus.

Oxytocin (choice D) is a hypothalamic hormone that stimulates contraction of smooth muscle in the uterus and mammary glands. It has no effect on the ductus arteriosus.

A cyanotic infant is discovered to have a ventricular septal defect, an overriding aorta, right ventricular hypertrophy, and complete pulmonic stenosis. Which of the following accompanying congenital anomalies permits survival in this patient?

A. Bicuspid aortic valve 
B. Ostium secundum defect
C. Patent ductus arteriosus
D. Patent foramen ovale
E. Preductal coarctation of aorta 

The correct answer is C. The ductus arteriosus connects the aorta with the pulmonary artery. If it remains patent after birth, it allows oxygenated blood to flow from the aorta to the pulmonary artery. In this patient with tetralogy of Fallot with complete right ventricular outflow obstruction, this anastomosis is a crucial source of blood to the pulmonary vasculature. 

A bicuspid aortic valve (choice A) may be asymptomatic but can lead to infective endocarditis, left ventricular overload, and sudden death. It is a common cause of aortic stenosis. It would not benefit a patient with tetralogy of Fallot in any way. 

Ostium secundum defect (choice B) is the most common form of atrial septal defect (ASD). ASD is an acyanotic congenital heart disease that would not improve cardiovascular function in a patient with tetralogy of Fallot. 

A patent foramen ovale (choice D) is a slit-like remnant of communication between the left and right atria in the fetus. It is usually not of clinical significance. 

A preductal coarctation of the aorta (choice E) involves narrowing of the aorta proximal to the opening of the ductus arteriosus. This would prevent adequate blood flow through a possible life-preserving PDA and would result in the patient's demise.

An x-ray performed on a newborn infant shows enlargement of the left ventricle and left atrium as well as dilatation of the aorta. Echocardiographic studies demonstrate volume-overloading of the left ventricle. Cardiac auscultation reveals the presence of a continuous "machinery" murmur. Which of the following is the most likely diagnosis?

A. Atrial septal defect
B. Patent ductus arteriosus
C. Pulmonic stenosis
D. Tetralogy of Fallot
E. Ventricular septal defect

The correct answer is B. Patent ductus arteriosus (PDA) is a congenital cardiac disorder in which blood traveling in the aorta is shunted through the ductus arteriosus to the pulmonary arteries. On x-ray, the left ventricle and left atrium may be enlarged, and pulmonary hypertension may be observed. PDA is characterized by a continuous "machinery" murmur on auscultation. If the ductus is widely patent, pulmonary hypertension may eventually develop, and the initially left-to-right shunt is reversed, sending deoxygenated blood through the descending aorta, and producing cyanosis (Eisenmenger syndrome). Since the deoxygenated blood enters the descending aorta, the toes can be cyanotic, but the fingers are generally not.

In atrial septal defect (choice A), left-to-right shunting causes volume overloading of the right ventricle, the increased flow across the pulmonic valve producing a midsystolic pulmonary ejection murmur. The second heart sound is widely split. A diastolic murmur may also be heard, reflecting increased flow from the right atrium into the right ventricle.

Pulmonic stenosis (choice C) typically produces a harsh systolic ejection murmur best heard at the upper left sternal border, often preceded by a systolic ejection sound.

Tetralogy of Fallot (choice D) is a form of cyanotic congenital heart disease characterized by ventricular septal defect, right ventricular outflow tract obstruction, an overriding aorta, and right ventricular hypertrophy. The heart is often described as "boot-shaped" on chest x-ray.

A ventricular septal defect (choice E) would produce an initial left-to-right shunt, characterized by a holosystolic murmur, and increased pulmonary vascularity on chest x-ray. A mid-diastolic rumble may also be heard.
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Pyloric Stenosis 
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Hypertrophic pyloric stenosis is obstruction of the pyloric lumen due to pyloric muscular hypertrophy.

The pylorus, or pyloric part, is the region of the stomach that connects to the duodenum (not to be confused with the pyloric glands, which are analogous to the gastric glands (although currently referred to as the fundic glands)). The pylorus is considered as having two parts, the pyloric antrum (opening to the body of the stomach) and the pyloric canal (opening to the duodenum). The pyloric canal ends as the pyloric orifice, which marks the junction between the stomach and the duodenum. The orifice is surrounded by a sphincter, a band of muscle, called the pyloric sphincter.

Hypertrophic pyloric stenosis may cause almost complete gastric outlet obstruction. It affects 2 to 3 out of 1000 infants and is more common among males by a 5:1 ratio, particularly firstborn males. It occurs most often between 3 wk and 6 wk of age and rarely after 12 wk. The exact etiology is uncertain, but a genetic component is likely because siblings and offspring of affected people are at increased risk, particularly monozygotic twins. Maternal smoking during pregnancy also increases risk. Proposed mechanisms include lack of neuronal nitric oxide synthase, abnormal innervation of the muscular layer, and hypergastrinemia. Infants exposed to certain macrolide antibiotics (eg, erythromycin) in the first few weeks of life are at significantly increased risk.

Symptoms and Signs
Symptoms typically develop between 3 wk and 6 wk of life. Projectile vomiting (without bile) occurs shortly after eating. Until dehydration sets in, children feed avidly and otherwise appear well, unlike many of those with vomiting caused by systemic illness. Gastric peristaltic waves may be visible, crossing the epigastrium from left to right. A discrete, 2- to 3-cm, firm, movable, and olive-like pyloric mass is sometimes palpable deep in the right side of the epigastrium. With progression of illness, children fail to gain weight, and dehydration develops (see Symptoms and Signs).

Diagnosis
• Ultrasonography
Hypertrophic pyloricstenosis should be suspected in all infants in the first several months of life with projectile vomiting. Diagnosis is by abdominal ultrasonography showing increased thickness of the pylorus (typically to ≥ 4 mm; normal, < 2 mm) along with an elongated pylorus (> 16 mm). If the diagnosis remains uncertain, ultrasonography can be repeated serially or an upper GI series can be done, which typically shows delayed gastric emptying and a string sign or railroad track sign of a markedly narrowed, elongated pyloric lumen. In rare cases, upper endoscopy is required for confirmation. The classic electrolyte pattern of an infant with pyloricstenosis is that of hypochloremic metabolic alkalosis (due to loss of hydrochloric acid and simultaneous hypovolemia—see Metabolic Alkalosis). About 5 to 14% of infants have jaundice, and about 5% have malrotation (see Malrotation of the Bowel).

Treatment
• Surgery (pyloromyotomy)
Initial treatment is directed at hydration and correcting electrolyte abnormalities. Definitive treatment is a longitudinal pyloromyotomy, which leaves the mucosa intact and separates the incised muscle fibers. Postoperatively, the infant usually tolerates feeding within a day.

Key Points
• Projectile vomiting occurs shortly after feeding in an infant < 3 mo old.
• Diagnosis is by ultrasonography.
• Treatment is surgical incision of the hypertrophied pyloric muscle.

CLINICAL VIGNETTES

A 1-month old boy is brought to the emergency department by his mother, who states that he has been having what she describes as "projectile vomiting" for the past several days. She states that he vomits every time she feeds him, and the situation seems to be getting worse, although he does not seem to be in pain. She describes the vomitus as non-bilious, and he has had normal stools with no blood in them. On examination, the infant appears to be mildly dehydrated, his abdomen is soft, and there is a palpable, olive-sized, firm moveable mass in the right upper quadrant. Which of the following is the most likely diagnosis?

A. Duodenal atresia 
B. Intussusception 
C. Hirschsprung disease 
D. Midgut volvulus 
E. Pyloric stenosis 

E. Pyloric stenosis develops in the first weeks of life. It is caused by hypertrophy of the pyloric muscle, which obstructs gastric outflow. The incidence is higher in males and first-born infants. The symptoms include progressively worsening vomiting, which becomes projectile and is non-bilious. On examination, peristaltic waves may be seen, and an olive-sized mass is usually palpated in the right upper quadrant. 

Duodenal atresia (choice A) is usually associated with other congenital anomalies. Symptoms include bilious vomiting, abdominal distention, and failure to pass meconium. Upright abdominal x-ray films show the classic "double-bubble sign." 

Intussusception (choice B) presents with vomiting, bloody stool, and colicky abdominal pain. As the obstruction progresses, the vomitus becomes bile-stained. On examination, there is usually a sausage-shaped mass in the distribution of the colon. 

Hirschsprung disease (choice C), or aganglionic megacolon, is associated with failure to pass meconium or constipation and abdominal distention. Diagnosis is made by rectal biopsy. 

Midgut volvulus (choice D) can occur at any age but is common in infancy. Symptoms include bilious vomiting, abdominal distention, pain, and bloody stools. An upper gastrointestinal series is diagnostic for volvulus showing a "corkscrew" narrowing of the distal duodenum. 

A 4-week-old boy is brought to your office by his mother because he has had increasing amounts of vomiting over the past week. Initially it started as "spitting up" after a few meals a day, but now the baby is having projectile vomiting after every meal. She says the vomitus is non-bloody and non-bilious and the baby appears hungry after he vomits. This is her first child and she is not sure if this is normal. Physical examination is unremarkable. Laboratory studies show:  SQ 443

Sodium 140 mEq/L (N 135 - 145)
Potassium 3.0 mEq/L (N 3.5 - 5.0)
Chloride 87 mEq/L (N 98 - 106)
Bicarbonate 30 mEq/L (N 23 - 28)

At this time the most appropriate next step is to

A. do nothing
B. obtain an abdominal radiograph
C. obtain an abdominal ultrasound
D. order a barium enema
E. order a CT scan of the abdomen
F. order a upper gastrointestinal series with small bowel follow through

The correct answer is C. This baby has presented with the typical picture of pyloric stenosis. Projectile non-bilious vomiting is seen in virtually all patients. Patients also often develop a hypokalemic, hypochloremic metabolic alkalosis from the persistent vomiting. On exam, the upper abdomen may be distended after feeding and prominent peristaltic waves from left to right may be seen. The classic physical exam finding of an "olive-shaped" mass in the epigastric area is not always felt. An ultrasound is the least invasive, safest diagnostic test. The typical appearance on ultrasound is a hypoechoic ring with a hyperdense center. The pyloric muscle thickness measures greater than 4mm.

Since this patient has the symptoms of pyloric stenosis, it is inappropriate to do nothing (choice A).

A plain film of the abdomen (choice B) will most likely appear normal unless there is a complete obstruction of the pyloric outlet. Again, this study would expose the baby to unnecessary radiation. And, in this case, it would not help you to establish the diagnosis.

A barium enema (choice D) will not help to make the diagnosis in this patient. The fact that the vomitus is non-bilious puts the point of obstruction prior to the entrance of the sphincter of Oddi. A study performed from below will not help to see what is happening so high in the intestinal tract. If you suspected intussusception (paroxysmal abdominal pain, vomiting, diarrhea, heme-positive stool, and sausage-shaped mass in upper mid abdomen on palpation), then a barium enema (or air enema) would be both diagnostic and therapeutic.

An abdominal CT scan (choice E) is also not helpful in this case. A good study may show the thickening of the pylorus muscle (depending on the cut), but an ultrasound is a much quicker and cheaper study with no radiation exposure.
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Ulcerative Colitis  
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Ulcerative colitis (UC) is a chronic inflammatory and ulcerative disease arising in the colonic mucosa, characterized most often by bloody diarrhea. Extraintestinal symptoms, particularly arthritis, may occur. Long-term risk of colon cancer is high. Diagnosis is by colonoscopy. Treatment is with 5-aminosalicylic acid, corticosteroids, immunomodulators, anticytokines, antibiotics, and occasionally surgery.

Pathophysiology
UC usually begins in the rectum. It may remain localized to the rectum (ulcerative proctitis) or extend proximally, sometimes involving the entire colon. Rarely, it involves most of the large bowel at once.

The inflammation caused by UC affects the mucosa and submucosa, and there is a sharp border between normal and affected tissue. Only in severe disease is the muscularis involved. Early in the disease, the mucous membrane is erythematous, finely granular, and friable, with loss of the normal vascular pattern and often with scattered hemorrhagic areas. Large mucosal ulcers with copious purulent exudate characterize severe disease.

Symptoms and Signs
Bloody diarrhea of varied intensity and duration is interspersed with asymptomatic intervals. Usually an attack begins insidiously, with increased urgency to defecate, mild lower abdominal cramps, and blood and mucus in the stools.

When ulceration is confined to the rectosigmoid, the stool may be normal or hard and dry, but rectal discharges of mucus loaded with RBCs and WBCs accompany or occur between bowel movements. Systemic symptoms are absent or mild. If ulceration extends proximally, stools become looser and the patient may have > 10 bowel movements per day, often with severe cramps and distressing rectal tenesmus, without respite at night. The stools may be watery or contain mucus and frequently consist almost entirely of blood and pus.

Systemic symptoms and signs, more common with extensive UC, include malaise, fever, anemia, anorexia, and weight loss.

Diagnosis
• Stool cultures and microscopy (to exclude infectious causes)
• Sigmoidoscopy with biopsy
Initial presentation: Diagnosis is suggested by typical symptoms and signs, particularly when accompanied by extraintestinal manifestations or a history of previous similar attacks.

In all patients, stool cultures for enteric pathogens should be done, and Entamoeba histolytica should be excluded by examination of fresh stool specimens. When amebiasis is suspected because of epidemiologic or travel history, serologic titers and biopsies should be done.

Sigmoidoscopy should be done; it allows visual confirmation of colitis and permits direct sampling of stool or mucus for culture and microscopic evaluation, as well as biopsy of affected areas. Although visual inspection and biopsies may be nondiagnostic, because there is much overlap in appearance among different types of colitis, acute, self-limited, infectious colitis can usually be distinguished histologically from chronic idiopathic UC or Crohn colitis. Severe perianal disease, rectal sparing, absence of bleeding, and asymmetric or segmental involvement of the colon indicate Crohn disease rather than UC. Colonoscopy is usually unnecessary initially but should be done electively if inflammation has extended proximal to the reach of the sigmoidoscope. 

Laboratory tests should be done to screen for anemia, hypoalbuminemia, and electrolyte abnormalities. Liver function tests should be done; elevated alkaline phosphatase and γ-glutamyl transpeptidase levels suggest possible primary sclerosing cholangitis. Perinuclear antineutrophil cytoplasmic antibodies are relatively specific (60 to 70%) for UC.

Prognosis

Colon cancer: The risk of colon cancer is proportional to the duration of disease and amount of colon affected but not necessarily to the clinical severity of the attacks. Some studies suggest that sustained microscopic inflammation is a risk factor, and that use of 5-ASA to control inflammation is protective. Cancer begins to appear by 7 yr from onset of illness in patients with extensive colitis. The cumulative likelihood of cancer is about 3% at 15 yr, 5% at 20 yr, and 9% at 25 yr, representing an annual risk of about 0.5 to 1% after the 10th yr. There is probably no higher absolute cancer risk among patients with childhood-onset colitis independent of the longer duration of disease. However, patients who have inflammatory bowel disease and primary sclerosing cholangitis are at a higher risk of cancer from the time of colitis diagnosis. 

Regular colonoscopic surveillance, preferably during remission, is advised for patients with disease duration > 8 to 10 yr (except for those with isolated proctitis). Endoscopic biopsies should be taken every 10 cm throughout the colon.

Treatment

• 5-Aminosalicylic acid (5-ASA)
• Corticosteroids
• Anticytokine drugs
• Sometimes surgery

Mild left-sided disease: Patients with proctitis, or colitis that does not extend proximally beyond the splenic flexure, are treated with 5-ASA (mesalamine) enemas once/day or bid depending on severity. Suppositories are effective for more distal disease and are usually preferred by patients. Corticosteroid and budesonide enemas are slightly less effective but should be used if 5-ASA is unsuccessful or not tolerated.

Moderate or extensive disease: Patients with inflammation proximal to the splenic flexure or left-sided disease unresponsive to topical agents should receive an oral 5-ASA formulation in addition to 5-ASA enemas. High-dose corticosteroids are added for more severe symptoms; after 1 to 2 wk, the daily dose is reduced by about 5 to 10 mg each wk. Immunomodulater therapy with azathioprine or 6-mercaptopurine can be used in patients who are refractory to maximal doses of 5-ASA and would otherwise need long-term corticosteroid therapy. Additionally, infliximab and adalimumab are beneficial in some patients and may be considered for those refractory to immunomodulator or corticosteroid therapy as well as those who are corticosteroid dependent. 

Severe disease: Patients with > 10 bloody bowel movements per day, tachycardia, high fever, or severe abdominal pain require hospitalization to receive high-dose IV corticosteroids. 5-ASA may be continued. IV fluids and blood transfusion are given as needed for dehydration and anemia. The patient must be observed closely for the development of toxic megacolon. Parenteral hyperalimentation is sometimes used for nutritional support but is of no value as primary therapy; patients who can tolerate food should eat. 

Maintenance therapy: After effective treatment of a flare-up, corticosteroids are tapered based on clinical response and then stopped because they are ineffective as maintenance. Patients should remain on 5-ASA drugs—oral or rectal, depending on location of disease—indefinitely because stopping maintenance therapy often allows disease relapse. Dosage intervals for rectal preparations may be gradually lengthened to every 2nd or 3rd day. There is ample evidence that combination oral and rectal therapy is significantly more effective than either therapy alone. 

Surgery: Nearly one third of patients with extensive UC ultimately require surgery. Total proctocolectomy is curative: Life expectancy and quality of life are restored to normal, the disease does not recur (unlike Crohn disease), and the risk of colon cancer is eliminated. 


Key Points
• UC begins in the rectum and may extend proximally in a contiguous fashion without intervening patches of normal bowel.
• Symptoms are intermittent episodes of abdominal cramping and bloody diarrhea.
• Complications include fulminant colitis, which may lead to perforation; long-term, the risk of colon cancer is increased.
• Treat mild to moderate disease with 5-ASA per rectum and, for proximal disease, by mouth.
• Treat extensive disease with high-dose corticosteroids or immunomodulator therapy with azathioprine or 6-mercaptopurine.
• Treat fulminant disease with high-dose IV corticosteroids or cyclosporine and antibiotics (eg, metronidazole, ciprofloxacin); colectomy may be required.
• About one third of patients with extensive UC ultimately require surgery.

CLINICAL VIGNETTES

A 34-year-old business man presents with a 3-month history of frequent episodes of loose stool preceded by left lower abdominal cramping. For the past 6 weeks, the stools have become increasingly bloody. On a number of occasions, he has had a sensation of rectal fullness but has been unable to pass any fecal matter. He travels extensively and has been to Asia, India, Pakistan, Germany, and Sweden in past year working on telecommunications infrastructure deals. On physical examination, he has mild tenderness in the left lower quadrant. A rectal examination reveals grossly bloody stools. A sigmoidoscopy reveals inflammation extending in a symmetric and circumferential pattern from the anal verge to the distal descending colon. Multiple stool tests are negative for bacterial and parasitic infections. Which of the following is the most likely cause of the patient's symptoms?

A. Crohn disease
B. Cytomegalovirus
C. Ischemic colitis
D. Ulcerative colitis
E. Yersinia enterocolitica

D. This patient has the typical subacute or chronic history of bloody diarrhea in association with left lower quadrant cramping. He also describes sensations of tenesmus. Although he has traveled extensively, multiple stool tests are negative for infectious etiology. Pathologically, ulcerative colitis is characterized by inflammation and often superficial ulceration that occur without skip lesions, beginning at the anal verge and extending varying distances proximally. Crohn disease (choice A) may produce a colitis but is more typically associated with right lower quadrant symptoms and ileitis. Cytomegalovirus (choice B) may cause a picture indistinguishable for ulcerative colitis but is usually seen only in immunocompromised patients, e.g., those with HIV who have low CD4 cell counts. Ischemic colitis (choice C) is usually a segmental colitis and does not usually start at the anal verge. It is more commonly seen in elderly patients or in those with hypercoagulable disorders. Yersinia enterocolitica(choice E) may produce diarrhea, infrequently bloody. However, Yersinia favors invasion of the terminal ileum and produces the acute onset of right lower quadrant symptoms.

A 28-year-old white woman comes to the office with an 8-month history of weight loss, fatigue, and diarrhea. She states that she has stools approximately 6 times per day and there is blood present in the majority of them. She denies any personal or family history of previous gastrointestinal problems. Her temperature is 37.2 C (99.1 F), blood pressure is 120/80 mm Hg, and pulse is 110/min. Physical examination reveals present normoactive bowel sounds. Her abdomen is soft with diffuse tenderness without rebound or guarding. An office sigmoidoscopy reveals friable mucosa with multiple bleeding points and no areas of normal mucosa. A colonic mucosal biopsy is likely to show

A. cobble stoning
B. skip lesions
C. superficial mucosal inflammation
D. transmural inflammation
E. villous atrophy

The correct answer is C. The clinical case describes ulcerative colitis, which is an inflammatory bowel disease that is characterized by weight loss, bloody stools, abdominal pain, and tenesmus. Sigmoidoscopy reveals mucosal inflammation that is continuous from a rectum proximal colon. A biopsy would most likely show superficial mucosal inflammation and ulceration.

Crohns disease is another type of inflammatory bowel disease that affects the entire thickness and will show transmural inflammation(choice D) of the wall of the colon. Cobble stoning (choice A) describes the gross appearance of the intestine in CD. CD need may occur anywhere from mouth to anus and usually has skip lesions (choice B) between areas of the normal intestine.

Villous atrophy (choice E) may be found in celiac sprue and malabsorption. It is not a typical feature of Crohns disease.
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Primary Sclerosing Cholangitis    
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Primary sclerosing cholangitis (PSC) is patchy inflammation, fibrosis, and strictures of the bile ducts that has no known cause. However, 80% of patients have inflammatory bowel disease, most often ulcerative colitis. Other associated conditions include connective tissue disorders, autoimmune disorders, and immunodeficiency syndromes, sometimes complicated by opportunistic infections. Fatigue and pruritus develop insidiously and progressively. Diagnosis is by cholangiography (magnetic resonance cholangiopancreatography or ERCP). Liver transplantation is indicated for advanced disease.

PSC is the most common form of sclerosingcholangitis. Most (70%) patients with PSC are men. Mean age at diagnosis is 40 yr.

Etiology
Although the cause is unknown, PSC is associated with inflammatory bowel disease, which is present in 80% of patients. About 5% of patients with ulcerative colitis and about 1% with Crohn disease develop PSC. This association and the presence of several autoantibodies (eg, anti–smooth muscle and perinuclear antineutrophilic antibodies [pANCA]) suggest immune-mediated mechanisms. T cells appear to be involved in the destruction of the bile ducts, implying disordered cellular immunity. A genetic predisposition is suggested by a tendency for the disorder to develop in multiple family members and a higher frequency in people with HLAB8 and HLADR3, which are often correlated with autoimmune disorders. An unknown trigger (eg, bacterial infection, ischemic duct injury) probably causes PSC to develop in genetically predisposed people.

Symptoms and Signs
Onset is usually insidious, with progressive fatigue and then pruritus. Jaundice tends to develop later. About 10 to 15% of patients present with repeated episodes of right upper quadrant pain and fever, possibly due to ascending bacterial cholangitis. Steatorrhea and deficiencies of fat-soluble vitamins can develop. Persistent jaundice harbingers advanced disease. Symptomatic gallstones and choledocholithiasis tend to develop in about 75% of patients. Some patients, asymptomatic until late in the course, first present with hepatosplenomegaly or cirrhosis. PSC tends to slowly and inexorably progress. The terminal phase involves decompensated cirrhosis, portal hypertension, ascites, and liver failure. The time from diagnosis to liver failure is about 12 yr.

Despite the association between PSC and inflammatory bowel disease, the two diseases tend to run separate courses. Ulcerative colitis may appear years before PSC and tends to have a milder course when associated with PSC. Similarly, total colectomy does not change the course of PSC.

The presence of both PSC and inflammatory bowel disease increases the risk of colorectal carcinoma, regardless of whether a liver transplantation has been done for PSC. Cholangiocarcinoma develops in 10 to 15% of patients.

Diagnosis
Magnetic resonance cholangiopancreatography (MRCP)
PSC is suspected in patients with unexplained abnormalities in liver function tests, particularly in those with inflammatory bowel disease. A cholestatic pattern is typical: elevated alkaline phosphatase and γ-glutamyltransferase (GGT) rather than aminotransferases. Gamma globulin and IgM levels tend to be increased. Anti–smooth muscle antibodies and pANCA are usually positive. Antimitochondrial antibody, positive in primary biliary cirrhosis, is characteristically negative.

Imaging of the hepatobiliary system begins with ultrasonography to exclude extrahepatic biliary obstruction. Although ultrasonography or CT can show ductal dilation, diagnosis requires cholangiography to show multiple strictures and dilations in the intrahepatic and extrahepatic bile ducts. Cholangiography should begin with magnetic resonance cholangiopancreatography (MRCP). ERCP is usually a 2nd choice because it is invasive. Liver biopsy is usually not required for diagnosis; when done, it shows bile duct proliferation, periductal fibrosis, inflammation, and loss of bile ducts. With disease progression, periductal fibrosis extends from the portal regions and eventually leads to secondary biliary cirrhosis.

Measurement of serum tumor markers and ERCP surveillance with brush cytology should be done regularly to check for cholangiocarcinoma.

Treatment
• Supportive care
• ERCP dilation for major (dominant) strictures
• Transplantation for recurrent bacterial cholangitis or complications of liver failure

Asymptomatic patients usually require only monitoring (eg, physical examination and liver function tests twice/yr). Ursodeoxycholic acid (eg, 5 mg/kg po tid, up to 15 mg/kg/day) reduces itching and improves biochemical markers but not survival. Chronic cholestasis and cirrhosis require supportive treatment. Episodes of bacterial cholangitis warrant antibiotics and therapeutic ERCP as needed. If a single stricture appears to be the major cause of obstruction (a dominant stricture, found in about 20% of patients), ERCP dilation (with brush cytology to check for tumors) and stenting can relieve symptoms.

Liver transplantation is the only treatment that improves life expectancy in patients with PSC and that offers a cure. Recurrent bacterial cholangitis or complications of end-stage liver disease (eg, intractable ascites, portosystemic encephalopathy, bleeding esophageal varices) are reasonable indications for liver transplantation.

Key Points
• Most (80%) patients with PSC have inflammatory bowel disease, usually ulcerative colitis, and many have autoantibodies.
• Suspect PSC if patients, particularly those with inflammatory bowel disease, have an unexplained cholestatic pattern of abnormalities in liver function tests.
• Exclude extrahepatic biliary obstruction by ultrasonography, then do MRCP (or, as a second choice, ERCP).
• Monitor patients with periodic liver function testing, and treat symptoms and complications (eg, • ERCP to dilate dominant strictures).
Consider liver transplantation if recurrent cholangitis or complications of liver failure develop.

CLINICAL VIGNETTES

A 30-year-old man with a 15-year history of ulcerative colitis develops intermittent cholestatic jaundice. Ultrasonographic examination fails to reveal gallstones. Liver biopsy demonstrates a large bile duct obstruction. Which of the following would most likely be seen on endoscopic retrograde cholangiopancreatography (ERCP)?

A. Beading of intrahepatic bile ducts
B. Markedly dilated common bile duct containing irregular radiolucent masses
C. Mass at the ampulla of Vater
D. Moderately dilated intrahepatic bile ducts and stricture in the bile duct at the porta hepatis
E. Very dilated biliary tree terminating in a blunt, nipple-like obstruction at the lower end of the common bile duct

Explanation:

The correct answer is A. The most likely diagnosis is primary sclerosing cholangitis, a disorder with a probable autoimmune component that is associated with ulcerative colitis (2/3 of primary sclerosing cholangitis patients have a history of ulcerative colitis). The disease is characterized by inflammation and fibrosis of the intrahepatic and extrahepatic bile ducts, producing alternating strictures and dilatation of the structures. These changes are seen as "beading" on endoscopic retrograde cholangiopancreatography.

Gallstones in the biliary tree produce irregular radiolucent masses (choice B).

Choice C describes the findings associated with carcinoma of the ampulla of Vater.

Choice D describes the findings associated with carcinoma of the extrahepatic bile ducts.

Choice E describes the findings associated with carcinoma of the pancreas.

A 32-year-old man presents complaining of severe pruritus over the past 2 weeks. He has a history of ulcerative colitis for the past 7 years, which has remained well controlled on sulfasalazine and cortisone enemas. His physical examination is unremarkable except for evidence of diffuse excoriations on his extremities and trunk. Laboratory studies reveal a mild iron deficiency anemia and normal electrolytes. Liver function tests are normal, except for an alkaline phosphatase that is 322 U/L (normal, <110 U/L). Which of the following is the most likely explanation for his symptoms?

A. Erythema nodosum 
B. Hepatitis C 
C. Primary biliary cirrhosis 
D. Primary sclerosing cholangitis 
E. Pyoderma gangrenosum 

D. This patient has had longstanding ulcerative colitis and has now developed pruritus in the setting of an elevated alkaline phosphatase. This is consistent with a diagnosis of primary sclerosing cholangitis, whose activity is not related to the activity of the associated ulcerative colitis. This sclerosing process involves both the intra- and extrahepatic ducts and is diagnosed by endoscopic retrograde cholangiopancreatography (ERCP). Primary sclerosing cholangitis occurs most often in young men and is commonly associated with inflammatory bowel disease, particularly ulcerative colitis. Classically, primary sclerosing cholangitis produces a triad of progressive fatigue, pruritus, and jaundice, although some patients will present with upper quadrant pain, fever, hepatosplenomegaly, or cirrhosis. The condition is worrisome because it may eventually progress to decompensated cirrhosis, portal hypertension, ascites, and liver failure. Treatment is generally supportive, with more specific measures as needed including antibacterial treatment for superimposed bacterial cholangitis, dilation by endoscopy or a transhepatic route of significant strictures, and ursodeoxycholic acid to relieve the pruritus. A variety of anti-inflammatory therapies (e.g., corticosteroids, azathioprine, methotrexate) have been tried but appear to have more adverse than beneficial effects. Liver transplantation appears to be the only true cure. 

Although erythema nodosum and pyoderma gangrenosum can be skin conditions seen in association with ulcerative colitis, they do not present with pruritus and, furthermore, have characteristic findings on physical examination. Erythema nodosum (choice A) presents as tender, red nodules, typically found on the lower extremities. Pyoderma gangrenosum (choice E) are pustular, ulcerating lesions, also generally found on the extremities, which can be very painful. 

There is no evidence of hepatocellular dysfunction or transaminase elevation, nor any history of hepatitis risk factors, so hepatitis C is unlikely (choice B). 

Primary biliary cirrhosis (choice C) does in fact present with pruritus and an elevated alkaline phosphatase; however, it is typically seen in middle-aged women and has no association with ulcerative colitis. 
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Henoch-Schonlein Purpura 
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Immunoglobulin A–associated vasculitis (IgAV—formerly called Henoch-Schönlein purpura-HSP) is vasculitis that affects primarily small vessels. It occurs most often in children. Common manifestations include palpable purpura, arthralgias, GI symptoms and signs, and glomerulonephritis. Diagnosis is clinical in children but usually warrants biopsy in adults. Disease is usually self-limited. Corticosteroids can relieve arthralgias and GI symptoms but do not alter the course of the disease. Progressive glomerulonephritis may require high-dose corticosteroids and cyclophosphamide.

IgA-containing immune complexes are deposited in small vessels of the skin and other sites, with consequent activation of complement. Possible inciting antigens include viruses that cause URIs, streptococcal infection, drugs, foods, insect bites, and immunizations. Focal, segmental proliferative glomerulonephritis is typical but mild.

Symptoms and Signs
The disease begins with a sudden palpable purpuric rash typically occurring on the feet, legs, and, occasionally, the trunk and arms. The purpura may start as small areas of urticaria that become palpable and sometimes hemorrhagic and confluent. Crops of new lesions may appear over days to several weeks. Many patients also have fever and polyarthralgia with periarticular tenderness and swelling of the ankles, knees, hips, wrists, and elbows.

GI symptoms are common and include colicky abdominal pain, abdominal tenderness, and melena. Intussusception occasionally develops in children. Stool may test positive for occult blood.

Symptoms usually remit after about 4 wk but often recur at least once after a disease-free interval of several weeks. In most patients, the disorder subsides without serious sequelae; however, some patients develop chronic renal failure.

Diagnosis
• Biopsy of skin lesions
IgAV is defined as vasculitis with IgA1-dominant immune deposits, affecting small vessels in the skin and GI tract and frequently causing arthritis. IgAV is also associated with glomerulonephritis indistinguishable from IgA nephropathy.

The diagnosis is suspected in patients, particularly children, with typical skin findings. It is confirmed by biopsy of skin lesions when leukocytoclastic vasculitis with IgA in the vessel walls is identified. Biopsy is unnecessary if clinical diagnosis is clear in children. Urinalysis is done; hematuria, proteinuria, and RBC casts indicate renal involvement.

CBC and renal function tests are done. If renal function is deteriorating, renal biopsy may help define the prognosis. Diffuse glomerular involvement or crescent formation in most glomeruli predicts progressive renal failure.

Treatment
Primarily corticosteroids and symptomatic measures
If the cause is a drug, it has to be stopped. Otherwise, treatment is primarily symptomatic. Corticosteroids (eg, prednisone 2 mg/kg up to a total of 50 mg po once/day) may help control abdominal pain and are occasionally needed to treat severe joint pain or renal disease. Pulse IV methylprednisolone followed by oral prednisone and cyclophosphamide can be given to attempt to control inflammation when the kidneys are severely affected. However, the effects of corticosteroids on renal manifestations are not clear.

Key Points
• IgAV is vasculitis that affects primarily small vessels and occurs in children.
• Manifestations can include purpuric rash, arthralgias, fever, abdominal pain, and melena.
• Symptoms usually remit after about 4 wk.
• Diagnose by biopsy.
• Treat symptoms and consider corticosteroids.

CLINICAL VIGNETTES

A mother brings her 5-year-old boy to the clinic because of a rash on his legs and buttocks that she noticed this morning. He has also been complaining that his "belly hurts," but has had no change in appetite. He had an upper respiratory tract infection and sore throat about 1 week ago. He has not had any fevers, recent weight loss or joint pain, and has not taken any medications. His temperature is 37.0 C (98.6 F). Physical examination shows mild periumbilical tenderness and multiple 3-6 mm raised erythematous lesions on his lower extremities and buttocks. The lesions do not blanch with pressure. His leukocyte count, hemoglobin, platelet count, and coagulation studies are normal. Urinalysis shows 3-5 RBCs per hpf. A rapid strep test is positive. The most likely diagnosis is

A. Henoch-Schönlein purpura
B. Idiopathic thrombocytopenic purpura
C. Kawasaki disease
D. Rocky Mountain spotted fever
E. Wiskott-Aldrich syndrome

The correct answer is A. This patient presents with a classic case of Henoch-Schönlein purpura (HSP). HSP is an Ig-A mediated vasculitis involving the small blood vessels (arterioles and venules) of the skin, GI tract, kidneys, and joints. It is the most common vasculitis affecting children. The mean age is 4-7 years of age with slight male predominance. About 50% of children have a preceding upper respiratory tract infection and about 75% have group A strep recovered from their oropharynx. The classic rash is described as palpable purpura concentrated on the buttocks and lower extremities, but rarely on the trunk. These children can also present with non-migratory arthritis, colicky abdominal pain, microscopic or gross hematuria indicative of nephritis, and males can present with scrotal swelling. These patients must have a normal or elevated platelet count. This is what differentiates HSP from idiopathic thrombocytopenic purpura (ITP) (choice B). ITP also presents with a purpuric rash, but these children have low platelet counts. It is thought that these children develop an autoantibody to the platelet surface after a viral illness.

Kawasaki disease (choice C) is also known as mucocutaneous lymph node syndrome. It is an acute febrile vasculitis, which primarily affects the medium-sized vessels with particular affinity to the coronary arteries. Children must meet certain diagnostic criteria to be given the diagnosis of Kawasaki disease. They include fever for at least 5 days, plus four of the following five criteria: bilateral conjunctival injection; injected pharynx/dry or fissured lips/strawberry tongue; edema/erythema of the hands and feet; non-vesicular truncal rash; and cervical lymphadenopathy. The patient in the vignette does not meet the criteria for Kawasaki disease.

Rocky Mountain spotted fever (choice D) is an infectious disease caused by the bacterium Rickettsia rickettsii. These patients will present with fever, headache, malaise, and the classic rash is maculopapular and begins on the extremities and spreads inward to the trunk and includes the palms and soles. The rash may become purpuric after several days.

Wiskott-Aldrich syndrome (choice E) is an X-linked recessive syndrome characterized by eczema, thrombocytopenia, petechiae, and recurrent infections. This presentation is quite different from the boy in this vignette.

A 7-year-old boy arrives at the emergency room in acute distress. Over the past 3 to 4 days he has become progressively ill with generalized fatigue and mild, mid-abdominal pain that have become steadily worse. On physical examination he has a maculopapular rash on his thighs and feet with some spread of the rash to his buttocks. The rash does not blanch and the some lesions near the ankles look petechial or bruised. His temperature is 39.0 C(102.2 F) and he is drawing his knees to his chest for relief of his stomach pains. He is nauseated and vomited once before coming to the hospital. He has semi-soft dark stool, which is guaiac-positive. The boy has not voided since early morning and cannot provide a urine sample. The doctor determines that he is 10% dehydrated and asks the nurse to start intravenous fluids. Which of the following is the most likely diagnosis?

A. Pancreatitis 
B. Rocky Mountain spotted fever 
C. Nephrotic syndrome 
D. Henoch-Schönlein Purpura 
E. Appendicitis 

D. Henoch- Schönlein Purpura (HSP) is the most likely diagnosis. This boy has abdominal pain with guaiac-positive stools, but also has a prominent rash, mostly on his lower extremities. Other characteristic findings of HSP include hematuria and joint pains. The illness may follow an upper respiratory infection or strep throat. The rash starts out as an urticarial rash and progresses to become petechial and purpuric. There may be a history of migratory joint pain and arthritis. Affected joints include ankles, knees, wrists, and elbows.

If the abdominal pain were described as epigastric with radiation to the back, pancreatitis (choice A) might have been the likely diagnosis.In children, pancreatitis is frequently associated with viral illnesses (e.g., mumps), drugs (e.g., sulfonamides), or underlying systemic disease (e.g., lupus). Although pancreatitis has been reported in association with HSP, it is not the most likely diagnosis. 

Rocky Mountain spotted fever (choice B) is one of the most common tick-borne diseases. The typical rash of RMSF appears within a week of the tick bite. It begins on the palms, soles, and extremities and spreads centrally. Severe headache and photophobia are common complaints. 

This child did not have the typical findings of nephrotic syndrome (choice C) including: proteinuria, edema, and oliguria. Nephrotic syndrome frequently follows an infectious illness. 

In the classic case of appendicitis (choice E) periumbilical pain progresses with localization to the right lower quadrant.Anorexia, nausea, vomiting and changes in bowel movements may all occur. Fever is typically low-grade and rash is not present.

A 6-year-old boy is brought to the office by his mother because of a "red rash" that she noticed today. She says that 3 days ago he had a cough, runny nose, and fever that responded to ibuprofen. In the office, his temperature is 37 C (98.6 F) and he has an erythematous, blanching macular rash on his legs. You diagnose him with a viral exanthem and advise the mother to encourage the child to drink liquids and to use ibuprofen as needed for fever. One week later, the mother brings the child back to the office and reports that the rash has "changed", he has developed colicky abdominal pain several times per day, and he is complaining of left knee pain. In the office, his temperature is 37.2 C (99 F), blood pressure is 100/65 mm Hg, pulse is 100/min, and respiratory rate is 15/min. A physical examination reveals palpable purpura of both lower extremities and a soft, non-tender abdomen. His left knee is painful on flexion, but it is not erythematous or warm, and there does not seem to be an effusion. His gait is normal. The most appropriate study at this time is

A. arthrocentesis
B. colonoscopy
C. cultures of blood, urine, and cerebrospinal fluid
D. urinalysis

The correct answer is D. This patient most likely has Henoch-Schonlein purpura (HSP), a small-vessel vasculitis seen most commonly in children between the ages of 2 and 8. The child's preceding upper respiratory tract infection, low-grade fever, and arthralgias are all common elements of this disease. The typical rash of HSP is an evanescent, erythematous, macular rash on the lower extremities that progresses over the course of days to petechiae and palpable purpura. These change in color from red to purple to brown before eventually fading, normally over the course of weeks. HSP is an IgA-mediated autoimmune vasculitis, which can cause tissue damage as a result of immune complex formation. Deposition of these immune complexes in the kidneys can lead to nephritis, which is the leading cause of permanent sequelae from HSP. End-stage renal disease is an uncommon but possible outcome. It is important to perform frequent urinalyses for early detection of kidney involvement.

The joint manifestations of HSP are commonly arthralgias without arthritis, and can last weeks to months. Residual joint disease is rare, and arthrocentesis (choice A) is not necessary as part of the diagnostic evaluation.

Immune complex deposition in the bowel wall can lead to colicky abdominal pain in the setting of HSP and can result in serious, life-threatening sequelae (e.g., intussusception, perforation). This child's abdomen is benign on examination, and his symptoms should be followed clinically. A colonoscopy (choice B) is not necessary at this time.

While petechiae and purpura can be manifestations of overwhelming infection, often due to N. meningitis, the time course of the disease, the well-appearance of the child, and his stable vital signs argue against an infectious cause of this child's symptoms. Thus, cultures from multiple body sites (choice C) are not warranted at this time.
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Hemophilia 
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Hemophilias are common hereditary bleeding disorders caused by deficiencies of either clotting factor VIII or IX. The extent of factor deficiency determines the probability and severity of bleeding. Bleeding into deep tissues or joints usually develops within hours of trauma. The diagnosis is suspected in a patient with an elevated PTT and normal PT and platelet count; it is confirmed by specific factor assays. Treatment includes replacement of the deficient factor if acute bleeding is suspected, confirmed, or likely to develop (eg, before surgery).

Hemophilia A (factor VIII deficiency), which affects about 80% of patients with hemophilia, and hemophilia B (factor IX deficiency) have identical clinical manifestations and screening test abnormalities. Both are X-linked genetic disorders. Specific factor assays are required to distinguish the two.

Etiology
Hemophilia is an inherited disorder that results from mutations, deletions, or inversions affecting a factor VIII or factor IX gene. Because these genes are located on the X chromosome, hemophilia affects males almost exclusively. Daughters of men with hemophilia are obligate carriers, but sons are normal. Each son of a carrier has a 50% chance of having hemophilia, and each daughter has a 50% chance of being a carrier.

Pathophysiology
Normal hemostasis requires > 30% of normal factor VIII and IX levels. Most patients with hemophilia have levels < 5%; some have extremely low levels (< 1%). The functional level (activity) of factor VIII or IX in hemophilia A and B, and thus bleeding severity, varies depending on the specific mutation in the factor VIII or IX gene.

Carriers usually have levels of about 50%; rarely, random inactivation of their normal X chromosome in early embryonic life results in a carrier having factor VIII or IX levels of < 30%.

Most patients with hemophilia who were treated in the early 1980s were infected with HIV due to contaminated factor concentrates. Occasional patients developed immune thrombocytopenia secondary to HIV infection, which exacerbated bleeding.

Symptoms and Signs
Patients with hemophilia bleed into tissues (eg, hemarthroses, muscle hematomas, retroperitoneal hemorrhage). The bleeding may be immediate or occur slowly, depending on the extent of trauma and plasma level of factor VIII or IX. Pain often occurs as bleeding commences, sometimes before other signs of bleeding develop. Chronic or recurrent hemarthroses can lead to synovitis and arthropathy. Even a trivial blow to the head can cause intracranial bleeding. Bleeding into the base of the tongue can cause life-threatening airway compression.

Severe hemophilia (factor VIII or IX level < 1% of normal) causes severe bleeding throughout life, usually beginning soon after birth (eg, scalp hematoma after delivery or excessive bleeding after circumcision). Moderate hemophilia (factor levels 1 to 5% of normal) usually causes bleeding after minimal trauma. In mild hemophilia (factor levels 5 to 25% of normal), excessive bleeding may occur after surgery or dental extraction.

Diagnosis
• Platelet count, PT, PTT, factor VIII and IX assays
Sometimes von Willebrand factor activity and antigen and multimer composition

Hemophilia is suspected in patients with recurrent bleeding, unexplained hemarthroses, or a prolongation of the PTT. If hemophilia is suspected, PTT, PT, platelet count, and factor VIII and IX assays are obtained. In hemophilia, the PTT is prolonged, but the PT and platelet count are normal. Factor VIII and IX assays determine the type and severity of the hemophilia.

Prevention
Patients should avoid aspirin and NSAIDs (both inhibit platelet function). Regular dental care is essential so that tooth extractions and other dental surgery can be avoided. Drugs should be given orally or IV; IM injections can cause hematomas. Patients with hemophilia should be vaccinated against hepatitis B.

Treatment
• Replacement of deficient factor
• Sometimes antifibrinolytics

Replacement of the deficient factor is the primary treatment. In hemophilia A, the factor VIII level should be raised.

In hemophilia B, factor IX can be given as a purified or recombinant viral-inactivated product every 24 h. The target levels of factor correction are the same as in hemophilia A.

Fresh frozen plasma contains factors VIII and IX. However, unless plasma exchange is done, sufficient whole plasma usually cannot be given to patients with severe hemophilia to raise factor VIII or IX to levels that prevent or control bleeding. Fresh frozen plasma should, therefore, be used only if rapid replacement therapy is necessary and factor concentrate is unavailable or the patient has a coagulopathy that is not yet defined precisely.

Key Points
• Hemophilias are x-linked recessive disorders of coagulation.
• Hemophilia A (about 80% of patients) involves factor VIII deficiency, and hemophilia B involves factor IX deficiency.
• Patients bleed into tissues (eg, hemarthroses, muscle hematomas, retroperitoneal hemorrhage) following minimal trauma; fatal intracranial hemorrhage may occur.
• The PTT is prolonged but the PT and platelet count are normal; factor VIII and IX assays determine the type and severity of the hemophilia.
• Patients with bleeding or in whom bleeding is anticipated (eg, before surgery or dental extraction) are given replacement factor, preferably using a recombinant product; dose depends on the circumstances.
• About 15 to 35% of patients with hemophilia A develop antibodies to factor VIII.

CLINICAL VIGNETTES

A 4-year old boy was brought to hospital with a swollen right knee. His only sibling, his sister mentioned that when they were playing this morning in the backyard, he jumped down off the slide and immediately complained of pain in his right knee. His mother then recalled that some months ago he bled for an unusually longer time following injury with a razor. The diagnosis of either hemophilia A or B was suspected and he was transfused with fresh plasma and scheduled for measurement of serum levels of factor VIII and factor IX. Awaiting these measurements, which of the following labs values would be consistent with a diagnosis of hemophilia?

[A] PTT is prolonged but the PT and platelet count are normal
[B] PT is prolonged but the PTT and platelet count are normal
[C] PT and PTT are prolonged but platelet count are normal
[D] PTT is prolonged and the platelet count is low
[E] PT is prolonged and the platelet count is low

A 5-year-old boy is brought to an emergency room because of a painful, swollen knee joint. The boy had fallen while playing, and the joint had subsequently begun to swell. The mother reports that the boy was known to have hemophilia 
B. Replacement of which of the following is indicated?

A. Factor C 
B. Factor S 
C. Factor VII 
D. Factor VIII 
E. Factor IX 

E. Hemophilia B is clinically very similar to hemophilia A, but is due to X-linked deficiency of blood clotting factor IX rather than VIII. This patient needs factor IX replacement to stop his bleeding. The method used for calculating the amount of Factor VIII to give in hemophiliac A patients is to multiply the patient's weight in pounds by 20 and then by the desired plasma level in units. If this algorithm is used in hemophiliac B patients to calculate factor IX levels, it is found that the actual achieved blood levels are only about half that expected, possibly because Factor IX tends to bind to the endothelium of the vessel walls. For this reason, it is important to either monitor the patient for cessation of bleeding or check clotting times before assuming that a calculated dose of Factor IX had its intended effect. Aspiration of blood out of a joint (such as in this case) is usually only attempted after the bleeding process is under control. 

Factor C (choice A) deficiency and Factor S (choice B) deficiency cause a thrombotic tendency. 

Factor VII (choice C) deficiency is a rare, autosomal recessive cause of serious bleeding. 

Factor VIII (choice D) deficiency causes hemophilia A. 
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Shaken Baby Syndrome  
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Shaken baby syndrome (SBS) is a form of child abuse. It refers to brain injury that happens to the child. It occurs when someone shakes a baby or slams or throws a baby against an object. A child could be shaken by the arms, legs, chest, or shoulders.

Some experts use the term shaken-impact syndrome. Many doctors use the term abusive head trauma to describe the injury and intentional head injury to describe how it happened.
Shaken baby syndrome often occurs when a baby won't stop crying and a caregiver who is frustrated shakes the baby. To help prevent this problem, learn healthy ways to relieve stress and anger. And carefully choose your child care providers.

Normal play, such as bouncing a child on a knee or gently tossing a child in the air, does not cause shaken baby syndrome.

Shaken baby syndrome may occur in children up to 5 years of age, but it is most common in babies younger than 1. Shaken baby syndrome can cause serious long-term problems.

What causes the brain injury?

Shaking or throwing a child, or slamming a child against an object, causes uncontrollable forward, backward, and twisting head movement. Brain tissue, blood vessels, and nerves tear. The child's skull can hit the brain with force, causing brain tissue to bleed and swell.
Young children are more likely to have brain injury when they are shaken or thrown because they have:
Heavy, large heads for their body size.
Weak neck muscles that do not hold up the head well.
Delicate blood vessels in their brains.

Symptoms
Symptoms vary among kids based on how old they are, how often they've been abused, how long they were abused each time, and how much force was used.
Mild injuries may cause subtle symptoms. A child may vomit or be fussy or grouchy, sluggish, or not very hungry. More severe injuries may cause seizures, a slow heartbeat, trouble hearing, or bleeding inside one or both eyes.
It is important to get help if something doesn't seem right with your baby. Shaken baby syndrome may cause only mild symptoms at first, but any head injury in a young child can be dangerous. A child who has trouble breathing, is unconscious, or has seizures needs hospital care right away.
Symptoms can start quickly, especially in a badly injured child. Other times, it may take a few days for brain swelling to show symptoms. Often the caregiver who shook the child puts the child to bed in the hope that symptoms will get better with rest. By the time the child gets to a doctor, the child needs urgent care. In some cases, the child may be in a coma before a caregiver seeks help.
Shaken children may also have other signs of abuse, such as broken bones, bruises, or burns.

Diagnosis
Shaken baby syndrome can be hard to detect, because often there aren't clear signs of abuse. A baby may vomit, have a poor appetite, or be fussy or sluggish. These symptoms may at first seem related to an infection, such as the flu or meningitis. Sadly, you may not find out that shaken baby syndrome caused your child's injury until repeated abuse or more severe harm occurs.
Doctors check for shaken baby syndrome in several ways. They ask for a child's medical history. They may also do a physical examination and blood tests. Imaging tests such as X-rays, a CT scan, or an MRI. can look for bleeding or other injury in the brain.
A doctor may also do tests to rule out other conditions. For example, a lumbar puncture. checks a baby's spinal fluid for signs of meningitis. Blood found in this sample could point to a shaking injury.
A doctor who suspects shaken baby syndrome must report it to the local child welfare officials, social services, or the police.
If you suspect child abuse and the child is not in immediate danger, call your local child protection agency or the police. Do not confront the person who may have abused the child. This may cause more harm to the child.

Treatment
A child with shaken baby syndrome needs to be in the hospital, sometimes in an intensive care unit (ICU). Oxygen therapy. may be used to help the child breathe. Doctors may give the child medicine to help ease brain swelling. Sometimes a cooling mattress will help lower the child's body temperature and reduce brain swelling too. A child who has severe bleeding in the brain may need surgery.
Depending on the symptoms, doctors may try seizure medicine, physiotherapy, or other treatments.

Infants who are shaken may have shaken baby (shaken impact) syndrome. This syndrome is caused by violent shaking, often followed by throwing the infant. Infants who are shaken may have no visible signs of injury and may appear to be sleeping deeply. This sleepiness is due to brain damage and swelling, which may result from bleeding between the brain and skull (subdural hemorrhage). Infants may also have bleeding in the retina (retinal hemorrhage) at the back of the eye. Ribs and other bones may be broken.

Effects of Shaken Baby syndrome include swelling of the brain, which can raise pressure inside the skull and damage delicate brain tissue. This increased intracranial pressure can cause full fontanelles in a baby.

CLINICAL VIGNETTES

A 2-month-old male infant, previously healthy, presents to the emergency room with a seizure and difficulty breathing noted by his father. Mother went to work, and left the infant with her husband and infant's 3-year-old sibling. Father states that he put the infant down for a nap and found him 1 hour later having a seizure. Father called mother to find out what to do, and she instructed him to call the emergency services. Emergency medical technicians found the infant pale and bradycardic, and intubated the child at the scene. In the community hospital, lorazepam was given to control ongoing seizure activity. Physical exam is unremarkable except for the neurologic exam, which reveals brisk reflexes and Glasgow Coma Scale of 10/15. Ophthalmologic exam reveals bilateral multilayer retinal hemorrhages. Skeletal survey reveals multiple rib fractures and 3 classic metaphyseal fractures. Which of the following is the most likely diagnosis?

A. Vitamin K Deficiency
B. Rickets
C. Febrile Seizure
D. Osteogenesis Imperfecta
E. Shaken Baby Syndrome

A 3-month old infant is brought to a pediatrician's office because of increased lethargy and irritability. When asked about the cause of the bruises on the baby’s shoulders, the parents state that the child rolled off the couch and fell on the floor one day prior to presentation. His parents report that the child has been previously healthy and is up to date on his vaccinations. He has been meeting his development milestones. His fontanelles are full. While in office the patient develops a tonic clonic seizure. Which of the following is the next appropriate step?

A. Obtain a head computerized tomography scan 
B. Perform a retinoscopic examination 
C. Check serum levels of ammonia 
D. Administer intravenous benzodiazepines 
E. Perform a lumbar puncture 

B. The child's story is worrisome for shaken baby syndrome, in which the symptoms may not correlate with the physical findings. This diagnosis should be considered in any infant presenting with a dissonant history suspicious of child abuse. The child's fontanelles are full, indicative of increased intracranial pressure. A retinoscopic examination will indicate if this is indeed the case, since blurred fundi would suggest increased pressure. 

A retinal exam will also be able to check for retinal hemorrhages, a common finding in shaken baby syndrome.

A retinoscopic examination can be done faster than a head CT (choice A). The patient may ultimately need a head CT but the eye examination should be done first. 

Ammonia levels (choice C) should be checked if hepatic encephalopathy is a consideration. This is a possibility if Reye syndrome is on the differential. The increased fontanelle pressure leads to a diagnosis of trauma.

Benzodiazepines may be needed (choice D) in the short term to stop the seizure, but it is important to determine the cause of the seizure before intervening. 

Because the patient has increased intracranial pressure (suggested by the full fontanelles), a lumbar puncture may cause uncal herniation and should be avoided (choice E).
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Polycythemia Vera 
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Polycythemia vera (PV) is an idiopathic chronic myeloproliferative disorder characterized by an increase in RBC mass, which often manifests as an increased Hct. There is an increased risk of thrombosis and, rarely, acute leukemia and myelofibrotic transformation. Hepatosplenomegaly may also occur. Diagnosis is made by CBC, testing for JAK2 mutations, and clinical criteria. Treatment involves phlebotomy, low-dose aspirin, myelosuppressive drugs for high-risk patients, and rarely stem cell transplantation.

PV may be slightly more common in men. The mean age at diagnosis is around 60 yr.

Pathophysiology
PV involves increased production of all cell lines, including RBCs, WBCs, and platelets. Thus, PV is sometimes called a panmyelosis because of elevations of all 3 peripheral blood components. Increased production confined to the RBC line is termed erythrocytosis; erythrocytosis may occur with PV but is more commonly due to other causes. In PV, RBC production proceeds independently of erythropoietin levels.

Extramedullary hematopoiesis may occur in the spleen, liver, and other sites that have the potential for blood cell formation. Peripheral blood cell turnover increases. Eventually, progression to a spent-phase may occur, with a phenotype indistinguishable from primary myelofibrosis. Transformation to acute leukemia is rare, although the risk is increased with exposure to alkylating agents, such as chlorambucil, and radioactive phosphorus (mostly of historic significance).

Complications: In PV, blood volume expands and hyperviscosity develops. Patients are prone to develop thrombosis. Thrombosis can occur in most blood vessels, resulting in stroke, transient ischemic attacks, deep venous thrombosis, MI, retinal artery or vein occlusion, splenic infarction (often with a friction rub), or Budd-Chiari syndrome. Previously, most experts believed hyperviscosity was the predisposing factor for thrombosis. Newer studies suggest that risk of thrombosis may be primarily related to the degree of leukocytosis. However, this hypothesis has yet to be confirmed in dedicated, prospective trials. 

Platelets may function abnormally, predisposing to increased bleeding. Increased cell turnover may cause hyperuricemia, increasing the risk of gout and urate kidney stones. 

Symptoms and Signs
PV itself is often asymptomatic. Occasionally, increased red cell volume and viscosity cause weakness, headache, light-headedness, visual disturbances, fatigue, and dyspnea. Pruritus often occurs, particularly after a hot bath. The face may be red and the retinal veins engorged. The palms and feet may be red, warm, and painful, sometimes with digital ischemia (erythromelalgia). Hepatomegaly is common, and > 75% of patients have splenomegaly (which may be massive).

Thrombosis may cause symptoms in the affected site (eg, neurologic deficits with stroke or transient ischemic attack, leg pain, swelling or both with lower extremity thrombosis, unilateral vision loss with retinal vascular occlusion).

Bleeding (typically GI) occurs in about 10% of patients.

Hypermetabolism can cause low-grade fevers and weight loss and suggests progression to spent-phase polycythemia, which is clinically indistinguishable from primary myelofibrosis.

Diagnosis
• CBC
• Sometimes bone marrow examination and serum erythropoietin level

PV is often first suspected because of an abnormal CBC (eg, Hb > 18.5 g/dL in men or > 16.5 g/dL in women), but it must be considered in patients with suggestive symptoms, particularly Budd-Chiari syndrome (however, some patients develop Budd-Chiari syndrome before the Hct increases). Neutrophils and platelets are often, but not invariably, increased; in patients with only elevated Hb, PV may be present, but secondary erythrocytosis, a more common cause of elevated Hb, must first be considered (see Secondary Erythrocytosis). PV should also be considered in the rare patient with a normal Hb level but microcytosis and evidence of iron deficiency; this combination of findings can occur with iron-limited hematopoiesis, which is a hallmark of some cases of PV.

When done, bone marrow examination typically shows panmyelosis, large and clumped megakaryocytes, and sometimes reticulin fibers. However, no bone marrow findings absolutely differentiate PV from other disorders of excessive erythrocytosis, such as congenital familial polycythemia.

Patients with PV typically have low or low-normal serum erythropoietin levels. Elevated levels suggest secondary erythrocytosis.

Treatment
• Possibly aspirin therapy
• Possibly phlebotomy
• Possibly myelosuppressive therapy
Because PV is the only form of erythrocytosis for which myelosuppressive therapy may be indicated, accurate diagnosis is critical. High-risk patients are > 60 yr and have a history of thrombosis or transient ischemic attacks (TIA) or both.

Aspirin: Aspirin 81 to 100 mg po once/day reduces the incidence of thrombotic complications. Thus, patients undergoing phlebotomy alone or phlebotomy and myelosuppression should be given aspirin unless contraindicated. Higher doses of aspirin may be associated with an increased risk of bleeding. 

Phlebotomy: Phlebotomy has been the mainstay of therapy for both high- and low-risk patients. Common thresholds for phlebotomy are Hct > 45% in men and >42% in women. A randomized controlled trial published in 2013 showed that patients randomized to a Hct < 45% had a significantly lower rate of cardiovascular death and thrombosis than did those with a target Hct of 45 to 50%. In a minority of patients with symptomatic rubor and hyperviscosity symptoms, phlebotomy can be therapeutic. 

Initially, 300 to 500 mL of blood are removed every other day.

Myelosuppressive therapy: Myelosuppressive therapy is indicated for high-risk patients. 

Hydroxyurea, which inhibits the enzyme ribonucleoside diphosphate reductase, is also used to achieve myelosuppression. 

Key Points
• Polycythemia vera (PV) is an idiopathic, chronic myeloproliferative disorder that involves increased production of all cell lines, including RBCs, WBCs, and platelets.
• Cause of PV appears to be a mutation of hematopoietic stem cells that leads to sustained activation of the JAK2 protein, which causes excess cell production.
• Complications include thrombosis, bleeding, and hyperuricemia; some patients eventually develop myelofibrosis or rarely, transformation to acute leukemia.
• PV is often first suspected because of an elevated Hb (> 18.5 g/dL in men, > 16.5 g/dL in women); neutrophils and platelets are often, but not invariably, increased.
• Test for JAK mutations and sometimes bone marrow examination and serum erythropoietin level and apply WHO criteria.
• Treatment must be individualized, but most patients should take aspirin; phlebotomy to target Hct < 45% is probably helpful; high-risk patients (age > 60 yr, history of thrombosis and/or transient ischemic attack) may benefit from myelosuppressive drugs (eg, hydroxyurea); JAK2 inhibitors are being tested.

CLINICAL VIGNETTES

A 55-year-old white male comes to your office with weakness and a headache. He also describes an annoying pruritus that occurs frequently after he takes a hot shower. The physical examination is remarkable for the presence of an enlarged spleen. He has a hemoglobin level of 21 g/dL (N 12–16) and a hematocrit of 63% (N 36–48). To confirm your clinical diagnosis, you obtain additional studies. Which one of the following would be most consistent with the most likely diagnosis in this patient?

A. A low serum erythropoietin level
B. A low platelet count
C. A low arterial oxygen concentration
D. An elevated carboxyhemoglobin level

A. Proliferation of the erythroid lineage in PV leads to suppression of renal erythropoietin  synthesis by a negative feedback mechanism. The patient described in this case has polycythemia vera. Pruritus after a hot shower (aquagenic pruritus) and the presence of splenomegaly helps to clinically distinguish polycythemia vera from other causes of erythrocytosis (hematocrit >55%). Specific criteria for the diagnosis of polycythemia vera include an elevated red cell mass, a normal arterial oxygen saturation (>92%), and the presence of splenomegaly. In addition, patients usually exhibit thrombocytosis (platelet count >400,000/mm3), leukocytosis (WBC >12,000/mm3), a low serum erythropoietin level, and an elevated leukocyte alkaline phosphatase score. High carboxyhemoglobin levels are associated with secondary polycythemia.

A 38-year-old man comes to the office because of increasing lethargy and fatigue over the past year. He is generally healthy and has no significant past medical history. He denies any shortness of breath, weight loss, or feelings of sadness or depression. He continues to be very active and exercises 4-5 times per week. His full neurological and physical examination is unremarkable. There is no clubbing or cyanosis. A 12-lead electrocardiogram and chest radiograph appear normal. His blood work is remarkable for a hematocrit of 59% and you call him to tell him the results. He should be told that he is at high risk for

A. bleeding
B. cor pulmonale
C. hypoxia
D. lymphoma
E. stroke

The correct answer is E. Polycythemia vera, idiopathic myelofibrosis, chronic myelogenous leukemia, and essential thrombocythemia are classified as chronic myeloproliferative disorders because they arise through the clonal expansion of a multipotent hematopoietic progenitor cell, with subsequent overproduction of one or more of the formed elements of the blood. Polycythemia vera is characterized by increased numbers of erythrocytes, granulocytes, and platelets. A major consequence of the increased hematocrit is hyperviscosity that has as its' primary manifestation, stroke.

Bleeding (choice A) is not a concern with these patients but is a useful therapy to decrease the magnitude of the viscosity symptoms that they suffer.

The presence of cor pulmonale (choice B) is seen when the primary etiology of the hypoxemia is pulmonary. In these cases, the increased pulmonary arterial pressures cause increased right ventricular pressures that lead to right heart failure and massive RV dilation. Patients with polycythemia vera have a primary overproduction of erythrocytes and therefore no cause of right heart failure or hypoxia (choice C).

There is no increased risk for lymphoma (choice D) but rather leukemia in these patients. All patients with myeloproliferative disorders have increased risk for degeneration into acute leukemia.
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Diverticulitis   
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Diverticulitis is inflammation of a diverticulum, which can result in phlegmon of the bowel wall, peritonitis, perforation, fistula, or abscess. The primary symptom is abdominal pain. Diagnosis is by CT. Treatment is with bowel rest, antibiotics (ciprofloxacin, or a 3rd-generation cephalosporin plus metronidazole), and occasionally surgery.

Diverticulitis occurs when a micro or macro perforation develops in a diverticulum, releasing intestinal bacteria. The resultant inflammation remains localized in about 75% of patients. The remaining 25% may develop abscess, free intraperitoneal perforation, bowel obstruction, or fistulas. The most common fistulas involve the bladder but may also involve the small bowel, uterus, vagina, abdominal wall, or even the thigh.

Diverticulitis is most serious in elderly patients, especially those taking prednisone or other drugs that increase the risk of infection. Nearly all serious diverticulitis occurs in the sigmoid.

Symptoms and Signs
Diverticulitis usually manifests with pain or tenderness in the left lower quadrant of the abdomen and fever. Peritoneal signs (eg, rebound or guarding) may be present, particularly with abscess or free perforation. Fistulas may manifest as pneumaturia, feculent vaginal discharge, or a cutaneous or myofascial infection of the abdominal wall, perineum, or upper leg. Patients with bowel obstruction have nausea, vomiting, and abdominal distention. Bleeding is uncommon.

Diagnosis
• Abdominal CT
• Colonoscopy after resolution

Clinical suspicion is high in patients with known diverticulosis. However, because other disorders (eg, appendicitis, colon or ovarian cancer) may cause similar symptoms, testing is required. Abdominal CT with oral and IV contrast is preferred, although findings in about 10% of patients cannot be distinguished from colon cancer. Colonoscopy, after resolution of the acute infection, is necessary for definitive diagnosis.

Treatment
• Liquid diet, oral antibiotics for mild disease
• IV antibiotics, npo for more severe disease
• CT-guided percutaneous drainage of abscess
• Sometimes surgery
A patient who is not very ill is treated at home with rest, a liquid diet, and oral antibiotics (eg, ciprofloxacin 500 mg bid amoxicillin/clavulanate 500 mg tid plus metronidazole 500 mg qid). Symptoms usually subside rapidly. Some recent data suggest some patients may recover from mild, acute, uncomplicated diverticulitis without antibiotic therapy. The patient gradually advances to a soft low-fiber diet for 4 to 6 wk. The colon should be evaluated after 6 to 8 wk with a colonoscopy or barium enema. After 1 mo, a high-fiber diet is resumed.

Patients with more severe symptoms (eg, pain, fever, marked leukocytosis) should be hospitalized, as should patients taking prednisone (who are at higher risk of perforation and general peritonitis). Treatment is bed rest, npo, IV fluids, and IV antibiotics (eg, ceftazidime 1 g IV q 8 h plus metronidazole 500 mg IV q 6 to 8 h).

About 80% of patients can be treated successfully without surgery. An abscess may respond to percutaneous drainage (CT guided). If response is satisfactory, the patient remains hospitalized until symptoms are relieved and a soft diet is resumed. A colonoscopy or barium enema is done ≥ 4 wk after symptoms have resolved.

Surgery: Surgery is required immediately for patients with free perforation or general peritonitis and for patients with severe symptoms that do not respond to nonsurgical treatment within 48 h. Increasing pain, tenderness, and fever are other signs that surgery is needed. Surgery should also be considered in patients with any of the following: ≥ 3 previous attacks of mild diverticulitis (or one attack in a patient < 50); a persistent tender mass; clinical, endoscopic, or x-ray signs suggestive of cancer; and dysuria or pneumaturia associated with diverticulitis in men (or in women who have had a hysterectomy) because this symptom may presage fistula formation or perforation into the bladder. 

The involved section of the colon is resected. The ends can be reanastomosed immediately in healthy patients without perforation, abscess, or significant inflammation. Other patients have a temporary colostomy with anastomosis carried out in a subsequent operation after inflammation resolves and their general condition improves. 

Key Points
• Diverticulosis is the presence of multiple diverticula in the colon; diverticulitis is inflammation of a diverticulum.
• Diverticulitis occurs when a diverticulum perforates, releasing intestinal bacteria.
• Inflammation remains localized in about 75% of patients; the remainder develop abscesses, free intraperitoneal perforation, bowel obstruction, or fistulas.
• Diagnose using abdominal CT with oral and IV contrast; do colonoscopy 6 to 8 wk after resolution to make definitive diagnosis.
• Management depends on severity but typically includes antibiotics and sometimes percutaneous or surgical drainage.

CLINICAL VIGNETTES

A 70-year-old man presents to the emergency department complaining of abdominal pain. He describes the pain as crampy and primarily in his left lower quadrant. He has had minimal nausea, but complains of constipation. His past medical history is significant for hypertension, hyperlipidemia, gout, and diverticulosis. His medications include atenolol and simvastatin. He is allergic to penicillin. His temperature is 38.0 C (100.4 F), blood pressure is 140/60 mm Hg, pulse is 100/min, and respirations are 20/min. His physical examination is significant for tenderness to palpation at the left lower quadrant without rebound or guarding. His rectal examination is guaiac negative. His heart and lung examinations are unremarkable. Which of the following is the most likely diagnosis?

A. Appendicitis
B. Diverticulitis
C. Diverticulosis
D. Ischemic colitis
E. Sigmoid volvulus

B. The presence of cramping, left lower quadrant pain with a localizing examination in a patient with known diverticulosis associated with fever and constipation is a classic presentation of diverticulitis. Appendicitis (choice A) becomes less likely given that the patient's pain is localized in the left lower quadrant. The classic pain of appendicitis is localized to the right lower quadrant. Diverticulosis (choice C) is incorrect since this term refers only to the presence of diverticula. The inflammation of a diverticulum(a), as suggested by this patient's history and examination, is termed diverticulitis. Ischemic colitis (choice D) is unlikely given that this condition is typically associated with abdominal pain on examination that is out of proportion to the presenting complaint, post-prandial abdominal discomfort, and rectal bleeding. Sigmoid volvulus (choice E) is unlikely since we have not been informed that the patient has a large region of hyperresonance over his abdomen, as would be expected with the bowel distension seen with volvulus.

A 70-year-old man presents with severe acute abdominal pain. Physical examination reveals tenderness with guarding localized to the left lower quadrant. A complete blood count with differential shows a white count of 18,000/mm3 with increased neutrophil band forms. Paracentesis demonstrates mixed flora bacteria with many neutrophils in the peritoneal fluid. Which of the following is the most probable source of the infection?

A. Bladder infection
B. Colonic diverticulum
C. Prostatic inflammation
D. Ruptured appendix
E. Ureteral stone

The correct answer is B. Diverticula that become impacted with fecaliths (undigested food residues) can become inflamed and perforate, causing the equivalent of appendicitis, but typically involve the left rather than right lower quadrant. This complication of diverticulitis can produce acute peritonitis, evidenced by the abdominal tenderness, guarding, and leukocytosis, and can kill elderly debilitated patients. Diagnostic paracentesis may be valuable in determining if perforation has occurred.

Bladder infection (choice A), usually related to an enlarged prostate, is common in elderly men, but does not usually cause peritonitis.

Prostatic inflammation (choice C) or infection does not usually spread to the abdomen.

Acute appendicitis (choice D) is usually a disease of young adults and is characterized by tenderness in the right lower quadrant.

Ureteral stones (choice E) can cause severe abdominal pain but do not usually cause peritonitis.

55-year-old woman is brought to the emergency department by her daughter because of left lower quadrant abdominal pain, anorexia, fever, and chills for the past 24 hours. Her temperature is 38.7 C (101.6 F), pulse is 110/min, and respirations are 18/min. She is awake and alert, although she appears uncomfortable. Examination shows hypoactive bowel sounds and a soft abdomen with mild voluntary guarding especially in the left lower quadrant. Digital rectal examination is significant for heme-positive stool. An electrocardiogram shows a sinus tachycardia at 110 beats per minute. There are no ST segment changes when compared with old electrocardiograms. A chest x-ray shows no acute disease. Abdominal x-ray demonstrates no air under the diaphragm and no ileus. A complete blood count, biochemical profile, cardiac enzymes, amylase, and lipase are drawn, but results are not yet available. The most appropriate initial management of this patient is to

A. admit for intravenous antibiotics, nil per os diet, and abdominal CT scan
B. discharge to home on a clear liquid diet and PO antibiotics
C. immediately refer to a gastroenterologist for colonoscopy
D. prepare the patient for immediate surgical exploration
E. send patient for urgent cardiac catheterization

The correct answer is A. This patient most likely has diverticulitis, an inflamed herniation of the mucosa of the colon through the muscular layer of the bowel wall. The best way to diagnose diverticulitis is with an abdominal CT scan. The appropriate management of this patient is admission to the hospital. She should be kept NPO and given IV antibiotics.

Mild cases of diverticulitis may be treated as an outpatient with a clear liquid diet and PO antibiotics (choice B). However, this patient is too sick to be discharged and ought to be treated with IV antibiotics.

A colonoscopy (choice C) is useful to diagnose diverticulosis, but would not be used during an acute attack of diverticulitis because of risk of perforation.

Indications for urgent surgical intervention include abscess formation, severe disease, or confirmed perforation. This patient does not yet show signs of needing surgical intervention (choice D).

Abdominal pain is often the presenting sign of cardiac ischemia. However, this patient has few risk factors, no EKG changes, and does have abdominal exam findings. Therefore, cardiac catheterization (choice E) would not be indicated. You should, however, still continue to monitor her cardiac function and obtain cardiac enzymes.
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Cholecystitis    
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Acute Cholecystitis is inflammation of the gallbladder that develops over hours, usually because a gallstone obstructs the cystic duct. Symptoms include right upper quadrant pain and tenderness, sometimes accompanied by fever, chills, nausea, and vomiting. Abdominal ultrasonography detects the gallstone and sometimes the associated inflammation. Treatment usually involves antibiotics and cholecystectomy.

Acute cholecystitis is the most common complication of cholelithiasis. Conversely, ≥ 95% of patients with acute cholecystitis have cholelithiasis. When a stone becomes impacted in the cystic duct and persistently obstructs it, acute inflammation results. Bile stasis triggers release of inflammatory enzymes (eg, phospholipase A, which converts lecithin to lysolecithin, which then may mediate inflammation). The damaged mucosa secretes more fluid into the gallbladder lumen than it absorbs. The resulting distention further releases inflammatory mediators (eg, prostaglandins), worsening mucosal damage and causing ischemia, all of which perpetuate inflammation. Bacterial infection can supervene. The vicious circle of fluid secretion and inflammation, when unchecked, leads to necrosis and perforation. If acute inflammation resolves then continues to recur, the gallbladder becomes fibrotic and contracted and does not concentrate bile or empty normally—features of chronic cholecystitis.

Acute acalculous cholecystitis: Acalculous cholecystitis is cholecystitis without stones. It accounts for 5 to 10% of cholecystectomies done for acute cholecystitis. Risk factors include the following: 

Critical illness (eg, major surgery, burns, sepsis, or trauma)
Prolonged fasting or TPN (both predispose to bile stasis)
Shock
Immune deficiency
Vasculitis (eg, SLE, polyarteritis nodosa)
The mechanism probably involves inflammatory mediators released because of ischemia, infection, or bile stasis. Sometimes an infecting organism can be identified (eg, Salmonella sp or cytomegalovirus in immunodeficient patients). In young children, acute acalculous cholecystitis tends to follow a febrile illness without an identifiable infecting organism. 

Symptoms and Signs
Most patients have had prior attacks of biliary colic or acute cholecystitis. The pain of cholecystitis is similar in quality and location to biliary colic but lasts longer (ie, > 6 h) and is more severe. Vomiting is common, as is right subcostal tenderness. Within a few hours, the Murphy sign (deep inspiration exacerbates the pain during palpation of the right upper quadrant and halts inspiration) develops along with involuntary guarding of upper abdominal muscles on the right side. Fever, usually low grade, is common.

In the elderly, the first or only symptoms may be systemic and nonspecific (eg, anorexia, vomiting, malaise, weakness, fever). Sometimes fever does not develop.

Acute cholecystitis begins to subside in 2 to 3 days and resolves within 1 wk in 85% of patients even without treatment.

Complications: Without treatment, 10% of patients develop localized perforation, and 1% develop free perforation and peritonitis. Increasing abdominal pain, high fever, and rigors with rebound tenderness or ileus suggest empyema (pus) in the gallbladder, gangrene, or perforation. When acute cholecystitis is accompanied by jaundice or cholestasis, partial common duct obstruction is likely, usually due to stones or inflammation. 

Diagnosis
• Ultrasonography
• Cholescintigraphy if ultrasonography results are equivocal or if acalculous cholecystitis is suspected
• Acute cholecystitis is suspected based on symptoms and signs.

Transabdominal ultrasonography is the best test to detect gallstones. The test may also elicit local abdominal tenderness over the gallbladder (ultrasonographic Murphy sign). Pericholecystic fluid or thickening of the gallbladder wall indicates acute inflammation.

Cholescintigraphy is useful when results are equivocal; failure of the radionuclide to fill the gallbladder suggests an obstructed cystic duct (ie, an impacted stone). False-positive results may be due to the following:

A critical illness
Receiving TPN and no oral foods (because gallbladder stasis prevents filling)
Severe liver disease (because the liver does not secrete the radionuclide)
Previous sphincterotomy (which facilitates exit into the duodenum rather than the gallbladder)
Morphine provocation, which increases tone in the sphincter of Oddi and enhances filling, helps eliminate false-positive results.

Abdominal CT identifies complications such as gallbladder perforation or pancreatitis.

Laboratory tests are done but are not diagnostic. Leukocytosis with a left shift is common. In uncomplicated acute cholecystitis, liver function tests are normal or only slightly elevated. Mild cholestatic abnormalities (bilirubin up to 4 mg/dL and mildly elevated alkaline phosphatase) are common, probably indicating inflammatory mediators affecting the liver rather than mechanical obstruction. More marked increases, especially if lipase (amylase is less specific) is elevated > 2-fold, suggest bile duct obstruction. Passage of a stone through the biliary tract increases aminotransferases (ALT, AST).

Acute acalculous cholecystitis: Acute acalculous cholecystitis is suggested if a patient has no gallstones but has ultrasonographic Murphy sign or a thickened gallbladder wall and pericholecystic fluid. A distended gallbladder, biliary sludge, and a thickened gallbladder wall without pericholecystic fluid (due to low albumin or ascites) may result simply from a critical illness. 

CT identifies extrabiliary abnormalities. Cholescintigraphy is more helpful; failure of a radionuclide to fill may indicate edematous cystic duct obstruction. Giving morphine helps eliminate a false-positive result due to gallbladder stasis. 

Treatment
• Supportive care (hydration, analgesics, antibiotics)
• Cholecystectomy
Management includes hospital admission, IV fluids, and analgesics, such as an NSAID (ketorolac) or opioid. Nothing is given orally, and nasogastric suction is instituted if vomiting or an ileus is present. Parenteral antibiotics are usually initiated to treat possible infection, but evidence of benefit is lacking. Empiric coverage, directed at gram-negative enteric organisms, involves IV regimens such as ceftriaxone 2 g q 24 h plus metronidazole 500 mg q 8 h, piperacillin/tazobactam 4 g q 6 h, or ticarcillin/clavulanate 4 g q 6 h.

Cholecystectomy cures acute cholecystitis and relieves biliary pain. Early cholecystectomy is generally preferred, best done during the first 24 to 48 h in the following situations:

The diagnosis is clear and patients are at low surgical risk.
Patients are elderly or have diabetes and are thus at higher risk of infectious complications.
Patients have empyema, gangrene, perforation, or acalculous cholecystitis.
Surgery may be delayed when patients have an underlying severe chronic disorder (eg, cardiopulmonary) that increases the surgical risks. In such patients, cholecystectomy is deferred until medical therapy stabilizes the comorbid disorders or until cholecystitis resolves. If cholecystitis resolves, cholecystectomy may be done ≥ 6 wk later. Delayed surgery carries the risk of recurrent biliary complications.

Percutaneous cholecystostomy is an alternative to cholecystectomy for patients at very high surgical risk, such as the elderly, those with acalculous cholecystitis, and those in an ICU because of burns, trauma, or respiratory failure.

Key Points
• Most (≥ 95%) patients with acute cholecystitis have cholelithiasis.
• In the elderly, symptoms of cholecystitis may be nonspecific (eg, anorexia, vomiting, malaise, weakness), and fever may be absent.
• Although acute cholecystitis resolves spontaneously in 85% of patients, localized perforation or another complication develops in 10%.
• Do ultrasonography and, if results are equivocal, cholescintigraphy.
• Treat patients with IV fluids, antibiotics, and analgesics; do cholecystectomy when patients are stable.

CLINICAL VIGNETTES

A 44-year-old obese woman presents to the emergency department complaining of 3 hours of severe abdominal pain. She has also had multiple episodes of vomiting during this time. She describes the pain as "worse than labor," and it radiates to the interscapular region. Her temperature is 38.9 C (102 F), and she has severe tenderness in her right upper quadrant. She reports that she has had multiple similar episodes in the past that have lasted approximately 30 minutes and then resolved spontaneously. Which of the following is most likely being obstructed by a gallstone?

A. Common bile duct 
B. Common hepatic duct 
C. Cystic duct 
D. Pancreatic duct 
E. Right hepatic duct 

C. This patient with acute cholecystitis has multiple risk factors, including female gender, obesity, and a classic history of prolonged biliary colic in association with fevers. The presentation illustrated is typical and results from obstruction of the cystic duct, which drains the gallbladder. 

Obstruction of the common bile duct (choice A) or the pancreatic duct (choice D) will produce acute bacterial cholangitis, which would be demonstrated by Charcot's triad, i.e., right upper quadrant pain, fever, and jaundice. 

Obstruction of either the common hepatic duct (choice B) or the right hepatic duct (choice E) may give a limited episode of cholangitis but will not cause cholecystitis, since the obstruction occurs in the biliary tree above the level of the entry of the cystic duct. 

A 43-year-old white woman presents to the emergency department with 1 day of increasingly severe pain localized to the right upper quadrant and radiating to the right lower scapula. She has also been experiencing nausea and vomiting. The woman has had similar, but milder, episodes of pain in the past, which had resolved spontaneously in a few days. Physical examination demonstrates involuntary guarding of abdominal muscles on the right. The gallbladder is palpable. Which of the following is the most appropriate next step in diagnosis?

A. CT scan 
B. Endoscopic retrograde cholangiography 
C. Esophagogastroduodenoscopy 
D. MRI scan 
E. Ultrasound 

E. The presentation is typical for acute cholecystitis, which occurs most frequently in the setting of cholelithiasis (gallstones). Other common features include an initially low-grade fever with neutrophilia and painful splinting during deep breathing. Serum amylase is typically elevated in gallstone pancreatitis. Seriously ill patients with high fever, rigors, or significant rebound tenderness may require urgent surgical intervention; in less seriously ill patients, it is feasible to establish the diagnosis and defer surgical intervention until after the acute episode has resolved. In most hospitals, ultrasound is ordered first, since this relatively inexpensive, fast, and noninvasive study can usually establish the presence of gallstones. In atypical cases, when acute cholecystitis without stones is present, cholescintigraphy using radioactive technetium 99m may be used to sequentially visualize the liver, extrahepatic bile ducts, gallbladder, and duodenum. 

CT (choice A) and MRI (choice D) scans are expensive and are usually not required for typical acute cholecystitis.

Endoscopic retrograde cholangiography (choice B) can be helpful in defining a small stone in the extrahepatic bile duct system, but it is not usually used as an initial test. 

Esophagogastroduodenoscopy (choice C) would not be helpful in classic gallstone disease, but might demonstrate a duodenal cancer compressing the ampulla of Vater if a patient with what appeared clinically to be gallstone disease had a negative ultrasound. 
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