Question 1

A 42-year-old woman comes to the office due to episodic diarrhea over the past several months.  The patient describes large-volume, watery diarrhea accompanied by flatulence, typically a few hours after a meal.  She has had no fever, abdominal pain, blood in stools, or nocturnal diarrhea.  The patient has a history of Hashimoto thyroiditis and takes levothyroxine.  She drinks a glass of wine every evening with dinner but does not use tobacco or illicit drugs.  The patient says she tries to eat a healthy diet despite a busy work schedule, frequently consuming fruits, vegetables, fish, and low-fat dairy products.  Vital signs are within normal limits.  The abdomen is soft, nondistended, and nontender with no hepatosplenomegaly.  Bowel sounds are normal.  The remainder of the examination shows no abnormalities.  Stool testing for occult blood is negative, and blood cell counts, serum electrolytes, and TSH levels are within normal limits.  Which of the following is the most appropriate response to the patient regarding her symptoms?

Accepted Answer

Explanation: This patient with chronic watery diarrhea, flatulence, and bloating after meals likely has lactose intolerance. Lactose intolerance is a common cause of adult-onset diarrhea due to malabsorption and typically presents in adults age 20-40. It is more common among patients of African, Latin American, Asian, and Native American descent. Lactose is processed into glucose and galactose by intestinal lactase on the brush border of the small intestine. Reduced activity of the lactase enzyme with age is the most common cause of lactose intolerance. Symptoms occur as the osmotic load of undigested carbohydrate passes through the intestines, drawing water into the lumen and decreasing transit time. In addition, colonic bacteria ferment lactose, creating short-chain fatty acids and hydrogen gas leading to bloating and flatulence. Lactose intolerance can be established in patients who have gastrointestinal symptoms after consuming lactose products and whose symptoms resolve after initiating a lactose-free diet. If the diagnosis remains in doubt, a lactose breath hydrogen test can be performed. Treatment consists of replacing lactose-rich foods (eg, milk, ice cream) with foods of relatively low lactose content (eg, yogurt, aged cheese) or supplementation with lactase. Calcium and vitamin D intake should be evaluated and supplemented if needed. (Choice A) Celiac disease also causes diarrhea and flatulence; however, patients typically describe foul-smelling, bulky diarrhea with steatorrhea and typically do not experience a temporal relation between mealtimes and gastrointestinal symptoms. In addition, iron deficiency anemia is a common finding in celiac disease. (Choice B) Irritable bowel syndrome results from poorly understood alterations in gastrointestinal tract motility. Patients typically have recurrent abdominal pain and changes in bowel habits (eg, small- to moderate-volume diarrhea). This patient's large-volume diarrhea occurring several hours after meals and her lack of abdominal pain are more consistent with lactose intolerance. (Choice C) Inflammatory bowel disease (eg, Crohn disease, ulcerative colitis) is frequently characterized by fatigue, weight loss, fever, and inflammatory diarrhea (eg, blood, mucus). Laboratory tests may show anemia and occult blood. (Choice E) Excessive alcohol use can cause chronic pancreatitis, which often leads to exocrine pancreatic insufficiency. Patients have impaired digestion of fat and protein and symptoms of steatorrhea. This patient's watery diarrhea (rather than steatorrhea) and absence of chronic abdominal pain make chronic pancreatitis less likely. Educational objective: Lactose intolerance is characterized by chronic watery diarrhea, bloating, and flatulence after lactose-containing meals. It is a common cause of diarrhea due to malabsorption and is due to insufficient lactase enzyme on the small intestine brush border. References: Lactose intolerance in adults: biological mechanism and dietary management. (http://www.ncbi.nlm.nih.gov/pubmed/26393648) Lactose intolerance: from diagnosis to correct management. (http://www.ncbi.nlm.nih.gov/pubmed/24443063)

Question 2

A 5-week-old boy is brought to the office by his mother due to vomiting.  The mother explains, "Over the past 4 days, my son has been vomiting forcefully right after drinking his formula.  He used to spit up after feeding, but it has been getting worse, and now, he seems to throw up everything he eats."  The emesis is the color of milk.  The patient has had fewer wet diapers today and a single stool yesterday.  He was born at 39 weeks gestation after an uncomplicated pregnancy.  Newborn metabolic screening was normal.  Medical history is notable for switching to formula at age 2 weeks due to low breast milk production.  At that time, the patient was at the 25th percentile for length, weight, and head circumference.  Today, he is at the 10th percentile for weight, although length and head circumference remain at the 25th percentile.  Temperature is 36.7 C (98.1 F) and pulse is 169/min.  Physical examination shows an awake, alert, slightly fussy infant.  The anterior fontanelle is open and mildly sunken.  The lips and mucous membranes are slightly dry.  Cardiopulmonary examination shows no abnormalities.  The abdomen is soft and nondistended with active bowel sounds, although waves of peristalsis are visible.  There is no hepatosplenomegaly or tenderness to palpation.  Serum chemistry is pending. The diagnosis is confirmed.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf40_8615_8f63_977e11c9a992_MD0005_00 This patient with pyloric stenosis has clinical signs of dehydration (eg, sunken fontanelle, dry mucous membranes) and needs rehydration with intravenous fluids. Moreover, protracted vomiting has likely caused hypokalemic, hypochloremic metabolic alkalosis in this patient, and infants who undergo surgery without first correcting the electrolyte imbalances are at increased risk for postoperative apnea. After fluid resuscitation and stabilization, surgical correction with a pyloromyotomy is indicated (Choice C). (Choice B) Given this patient's ongoing vomiting, oral rehydration is unlikely to be effective and will likely worsen his electrolyte derangements by causing further gastric hydrochloric acid loss. This infant should be NPO until after surgery. (Choice D) For vomiting caused by small bowel obstruction, a nasogastric tube placed to suction for bowel rest is a reasonable initial strategy for relieving pain and pressure and allowing partial obstructions to clear. However, this patient's obstruction is at the level of the stomach, and definitive surgical correction is required. Moreover, suctioning additional gastric contents would likely worsen this patient's hypochloremic metabolic alkalosis and does not address his dehydration Educational objective: In infants with pyloric stenosis, electrolyte derangements and dehydration must be corrected to stabilize the patient for pyloromyotomy and reduce the risk of postoperative apnea. References: Perioperative care of infants with pyloric stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/26490352)

Question 3

A 62-year-old Hispanic woman comes to the office with complaints of a sense of heaviness and discomfort in her right groin.  Her discomfort is worse with standing and coughing, and is relieved by lying flat.  She also noticed a painful bulging mass at the same site two days ago, which resolved spontaneously after two hours.  She has a past medical history of breast cancer and chronic bronchitis.  She had a left mastectomy at age 48 and two cesarean sections at 28 and 33 years of age.  She smokes a pack of cigarettes daily.  On examination and Valsalva maneuver, you find a right-sided femoral hernia that is easily reducible.  There is no evidence of incarceration or strangulation.  Which of the following is the most appropriate next step?

Accepted Answer

Explanation: A hernia is a small area of weakness or defect in the overlying muscular or fibrous wall through which abdominal contents pass. Groin hernias are either inguinal or femoral hernias. The most common presentation is the dull sensation of heaviness or discomfort that is more pronounced with prolonged standing or straining (increased intraabdominal pressure). These are easily reducible in most cases, and symptoms are relieved with lying flat. A dreaded complication is incarceration or strangulation. It occurs when a tight constriction ring forms around the herniated contents and the hernia then becomes irreducible. Patients typically present with a constant pain that gets worse over time. If left untreated, it leads to necrosis and gangrene of the contents, and can be life-threatening. A femoral hernia is much more predisposed to strangulation than an inguinal hernia. The effective treatment for all types of hernias is surgical repair. Risks of delaying the surgery are mainly those related to incarceration and strangulation. much more surgical repair (Choices A and B) Observation alone is not appropriate in patients with a femoral hernia. The risk of strangulation is the greatest in the early stages and with small hernias. (Choice D) Abdominal binders are only useful for symptomatic relief in patients with large incisional or umbilical hernias. These are not used for patients with femoral hernias. The only nonsurgical therapy for groin hernias is the use of a truss for symptom relief, but this is generally discouraged. (Choice E) Narcotic analgesics may mask the clinical features of strangulation. These should not be prescribed for long-term management of femoral hernias. Educational objective: The primary treatment for all types of hernias is surgical repair.

Question 4

A 40-year-old man comes to the clinic after having an abnormal laboratory evaluation during a blood donation program.  He had hepatitis B serologies as follows:  The patient has the same results on repeat testing at the office.  He is concerned that he has a serious liver disease that needs to be treated.  What is the next best step in management of this patient?

Accepted Answer

Explanation: This patient has an isolated elevation of anti-HBc, or total core antibody (includes IgM and IgG). This occurs in about 1% of blood donors in low prevalence areas such as the United States but in 10%-20% of donors in endemic areas. There are only 3 situations in which isolated anti-HBc may be seen: During the "window period" of acute hepatitis B virus (HBV) infection when HBsAg has fallen but anti-HBs has not yet risen. Patients may be symptomatic with a history of recent exposure but about 70% have subclinical hepatitis. IgM anti-HBc is typically positive and liver enzymes are elevated. Years after recovery from acute HBV infection once anti-HBs has waned off. Liver enzymes are normal and IgM anti-HBc is usually negative. After many years of chronic HBV infection when HBsAg has fallen to an undetectable level. Patients may have evidence of chronic liver disease and HBV DNA is detectable. IgM anti-HBc is typically negative. Once a patient with isolated anti-HBc has been identified, HBV serology (eg, anti-HBc, HBsAg, anti-HBs, anti-HBe) should initially be repeated to ensure that it is not a false positive result. If there are no changes in the results, IgM anti-HBc should be measured to determine if the infection is recent (as in the "window period" of acute hepatitis B). Liver function tests should also be performed, as an elevation in transaminase levels suggests an active infection. If liver enzymes are abnormal with negative IgM anti-HBc, or if there is evidence of chronic liver disease, HBV DNA should be obtained to evaluate for chronic HBV infection (Choice E). (Choice B) HBcAg should never be detected in the serum as it is present in infected hepatocytes only. (Choice C) An ultrasound would be appropriate for characterizing changes in the liver parenchyma and biopsy planning after a serologic diagnosis is made. (Choice D) HBV vaccination should not cause a rise in anti-HBc as the vaccine contains only the surface component. It should cause an isolated rise in the anti-HBs. Educational objective: Patients with an isolated elevation of anti-HBc should have hepatitis B serologies repeated to rule out a false positive result, followed by measurement of IgM anti-HBc and liver function tests to determine the acuity of infection. IgM anti-HBc may be the only diagnostic marker for acute HBV infection during the "window period." References: Hepatitis B: diagnosis and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/20387772) Hepatitis B virus infection. (http://www.ncbi.nlm.nih.gov/pubmed/24954675)

Question 5

A 2-week-old girl is brought to the office because she looks "a bit yellow."  She was born at 40 weeks gestation by normal spontaneous vaginal delivery to a mother whose blood type is AB+.  Apgar scores were 9 (-1 color) and 9 (-1 color) at 1 and 5 minutes, respectively.  Birth weight, length, and head circumference were at the 50th percentile.  She was discharged home on the second day of life and has been breastfeeding every 2-3 hours for 15 minutes on each side.  The infant has 6 wet diapers and 5-6 yellow seedy stools per day.  She has regained her birth weight and has normal vital signs.  Physical examination shows an active, crying infant with moist mucous membranes and jaundice of the face, neck, and chest.  The remainder of the examination is normal.  Total bilirubin is 10 mg/dL and direct bilirubin is 0.6 mg/dL. 
Which of the following is the most likely cause of this infant's hyperbilirubinemia?

Accepted Answer

Explanation: 11ec2b69_bf45_b63e_8f63_81201294615c_MD0005_00 Breast milk jaundice is a common cause of unconjugated hyperbilirubinemia in exclusively breast-fed infants that develops during the first 3-5 days of life and peaks by age 2 weeks. The etiology is thought to be due to high beta-glucuronidase activity in breast milk that deconjugates intestinal bilirubin and allows for increased intestinal absorption and enterohepatic circulation of bilirubin. Neonates are otherwise well-appearing, asymptomatic, and breastfeeding successfully. (Choice A) Alloimmune hemolytic disease of the newborn is typically caused by either ABO or Rh incompatibility between the fetus and mother. Risk factors include maternal blood type O and negative Rh status. Both ABO and Rh incompatibility are unlikely as the mother's blood type is AB+, indicating she has no antibodies against A, B, or Rh factor antigens. (Choice B) Biliary atresia presents as jaundice in the first 2 months of life due to conjugated hyperbilirubinemia (direct bilirubin >20% of total bilirubin) from progressive obstruction of the extrahepatic biliary tree. This infant has unconjugated hyperbilirubinemia, making this diagnosis unlikely. (Choice C) Breastfeeding failure jaundice occurs during the first week of life and is caused by lactation failure from inadequate milk supply, poor latch, or infrequent feeding. This decrease in oral intake results in decreased bilirubin elimination and increased intestinal absorption of bilirubin, thereby increasing serum bilirubin. This infant's age, normal weight, intake/output, and examination make this diagnosis unlikely. (Choice E) Gilbert syndrome typically manifests in adolescence as periodic asymptomatic jaundice from unconjugated hyperbilirubinemia. It rarely presents before puberty and is less common in girls, making this diagnosis less likely. Educational objective: Breast milk jaundice is a common cause of unconjugated hyperbilirubinemia that peaks at age 2 weeks in well-appearing and healthy neonates. In contrast, neonates with lactation failure typically present in the first week of life with jaundice, inadequate feeding, and dehydration. References: Management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation (http://www.ncbi.nlm.nih.gov/pubmed/15231951) Breastfeeding and jaundice. (http://www.ncbi.nlm.nih.gov/pubmed/11803412)

Question 6

A 3-month-old boy is brought to the office by his mother due to a "bulge in his groin."  The mother states that the bulge appears when the infant passes stool, but then it disappears without intervention.  The bulge does not appear to cause him any discomfort.  The infant is exclusively breastfed and nurses every 2 hours.  He rarely spits up and is voiding and stooling adequately.  The patient was born at 35 weeks gestation due to preterm premature rupture of membranes.  Pregnancy and delivery were otherwise uncomplicated.  Length and weight are at the 75th percentile.  Vital signs are normal.  The child is alert and smiling.  The abdomen is soft, nontender, and without hepatosplenomegaly.  The testes are descended bilaterally.  A 4-cm (1.6-in), nontender bulge appears in the right groin and extends toward the scrotum when the infant cries.  The mass has no discoloration or tenderness and is able to be gently pushed back into the groin.  The area appears normal once the child is consoled by his mother.  This patient's condition is associated with which of the following complications?

Accepted Answer

Explanation: 11ec2b69_bf3b_55ea_8f63_33d4e5209c20_MD0005_00 This infant has a groin mass that increases with abdominal pressure, consistent with an indirect inguinal hernia resulting from the failed obliteration of the processus vaginalis. Risk factors include prematurity, conditions that cause increased intraabdominal pressure (eg, prune belly syndrome), and concomitant genitourinary abnormalities (eg, cryptorchidism, hypospadias). processus vaginalis Most children are asymptomatic and present with a nontender, reducible mass (ie, reducible inguinal hernia). However, up to 13% of patients subsequently develop an incarcerated hernia, in which the mass is entrapped in the scrotum. The irreducible hernia can compromise blood supply to the entrapped intestines (bowel ischemia) and testis (impaired fertility, testicular atrophy). Signs of incarceration include vomiting, abdominal distension, and scrotal pain. Therefore, prompt surgical correction within 1-2 weeks is required for a reducible inguinal hernia, as a treatment delay of >2 weeks after diagnosis doubles the risk of incarceration. An incarcerated hernia is a surgical emergency requiring immediate repair. (Choice B) Chronic epididymitis can result from recurrent infection, inflammation, or urinary tract anomalies. This patient is afebrile and has no tenderness on examination, making infection unlikely. (Choice D) Testicular rupture typically occurs due to scrotal trauma. Patients present with severe scrotal pain and swelling following significant injury rather than a nontender, reducible scrotal mass. (Choices C and E) Malignant transformation and testicular torsion are sequelae of untreated cryptorchidism, which presents with an empty, poorly rugated scrotum due to an undescended testicle. Cryptorchidism is unlikely in this patient with palpable bilateral descended testes. Educational objective: Inguinal hernias in children typically present with a nontender, reducible groin mass. Without prompt surgical correction, the mass can become incarcerated and lead to complications such as bowel ischemia or testicular atrophy. References: Hernias and hydroceles. (http://www.ncbi.nlm.nih.gov/pubmed/24085793) Pediatric inguinal hernia, hydroceles, and undescended testicles. (http://www.ncbi.nlm.nih.gov/pubmed/22595705) Risk of incarceration of inguinal hernia among infants and young children awaiting elective surgery. (http://www.ncbi.nlm.nih.gov/pubmed/18981440)

Question 7

A 3-year-old boy is brought to the emergency department by his parents due to fatigue and refusal to eat.  His family recently arrived in the United States from Syria.  He has had watery diarrhea for the past several days but no fevers or vomiting.  His appetite has been decreased for several weeks.  Today, he has refused to eat but has drunk a few cups of water and juice.  Limited medical records show that tuberculosis skin testing was negative and catch-up vaccines were administered at the time of immigration.  Temperature is 36.1 C (97 F), blood pressure is 100/65 mm Hg, pulse is 100/min, and respirations are 22/min.  Height is 91 cm (36 in) and weight is 12 kg (26 lb 8 oz), corresponding to the 10th and 5th percentiles, respectively.  Physical examination shows a gaunt, tired-appearing boy.  Oral mucous membranes are dry but without ulcers or thrush.  He has bilateral pitting edema of the lower extremities, and his upper extremities have minimal subcutaneous fat.  A soft, vibratory heart murmur is heard on auscultation.  The lungs have no adventitious sounds.  The abdomen is mildly distended but otherwise soft and nontender.  Initial laboratory results are as follows:  Stool occult blood test is negative.  Which of the following is the most appropriate initial step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf43_1e2b_8f63_d7639972dbcc_MD0005_00 This patient has severe malnutrition with features of marasmus and kwashiorkor, including a thin, wasted (eg, minimal subcutaneous fat) appearance with pitting edema and fatigue. The patient is also mildly dehydrated (eg, dry mucous membranes) in the setting of an acute diarrheal illness. In a chronically malnourished and dehydrated child who is hemodynamically stable, as in this case, oral rehydration is the preferred method of rehydration. An orogastric or nasogastric tube supplying an oral rehydration solution (glucose and electrolytes) could be considered if oral intake is insufficient. marasmus and kwashiorkor Intravenous (IV) rehydration (Choice D) should be avoided in a stable, chronically malnourished patient due to risk of fluid overload and heart failure. If the patient is in hypovolemic shock, IV fluid volume is typically less (10 mL/kg) than a normal IV bolus (20 mL/kg) and should be administered over a slower period (eg, 30-60 minutes). (Choices A, C, and E) Feeding should be started cautiously in chronically malnourished patients to prevent refeeding syndrome (eg, hypophosphatemia, hypokalemia), which can be fatal. This patient already has decreased phosphate and potassium secondary to malnutrition and should therefore not be started initially on a high-calorie diet or total parenteral nutrition. He is also tolerating oral liquids and does not currently require aggressive methods of hydration. Educational objective: Oral rehydration is the preferred method of hydration in severe malnutrition. Intravenous rehydration can result in heart failure and should be used cautiously in cases of severe hypovolemia and shock. References: The effectiveness of interventions to treat severe acute malnutrition in young children: a systematic review. (http://www.ncbi.nlm.nih.gov/pubmed/22480797) Inpatient management of severe malnutrition: time for a change in protocol and practice. (http://www.ncbi.nlm.nih.gov/pubmed/21575313)

Question 8

A 32-year-old woman comes to the office due to abnormal liver imaging.  The patient went to the emergency department a week ago for severe right flank pain radiating to the groin.  A CT scan revealed a small ureter calculus, which she passed spontaneously the following day.  The scan also found a solitary liver lesion, and the patient was advised to follow up with her primary care physician.  She reports no right upper quadrant pain, nausea, jaundice, or clay-colored stool.  She has no chronic medical problems and has no history of surgery or blood product transfusions.  There is no history of cancer or liver disease in her family.  She has taken combined oral contraceptives for the past 8 years.  The patient does not use tobacco, alcohol, or illicit drugs.  She works in a bank, is in a monogamous relationship with her husband, and recently traveled to Europe for her honeymoon.  Vital signs are within normal limits.  There is no scleral icterus, mucosal lesions, lymphadenopathy, or skin rash.  Cardiopulmonary examination shows no abnormalities.  Bowel sounds are active in all quadrants.  The abdomen is nondistended, soft, and nontender.  Liver is not enlarged, and spleen is not palpable.  Laboratory results are as follows:  A CT scan of the abdomen reveals a 3-cm, well-demarcated lesion in the right lobe of the liver that shows peripheral enhancement with intravenous contrast administration.  There are no areas of hemorrhage, necrosis, or scarring.  The remainder of the liver is normal.  Which of the following is the most appropriate response to this patient regarding her liver lesion?

Accepted Answer

Explanation: 11ec2b69_bf3b_f22c_8f63_21b0d60f418b_MD0005_00 Hepatic adenoma is a benign epithelial tumor of the liver seen primarily in young women on combination oral contraception. Most cases are asymptomatic and discovered incidentally on imaging for other conditions, but tumors may grow large enough to cause episodic abdominal pain, rupture, or hemorrhage. Physical examination and laboratory tests are usually normal. Diagnosis is typically confirmed when CT scan of the abdomen reveals a well-demarcated lesion in the right lobe of the liver that shows peripheral enhancement with intravenous contrast (early phase). Hepatic adenomas <5 cm are often managed conservatively as the discontinuation of oral contraception can result in tumor regression. Those with larger or symptomatic adenomas usually require surgical resection. As malignant transformation can rarely occur, serial imaging and alpha-fetoprotein levels are typically required.(Choice A) Focal nodular hyperplasia is a benign liver lesion due to hyperplastic liver cells. Most cases arise in young women and are discovered incidentally on imaging for other conditions. However, CT scan with contrast usually shows uniform enhancement (not peripheral). (Choice B) Hepatic adenomas often bleed following needle biopsy, and the amount of tissue obtained is often insufficient for diagnosis. As such, needle biopsy is not typically performed. Suspected hepatic adenomas are usually diagnosed by imaging. (Choice C) Hepatic adenomas are benign lesions, and resection is only required in patients with symptoms or lesions >5 cm. Patients who are asymptomatic with lesions <5 cm do not require resection; they should discontinue oral contraception.(Choice E) Echinococcus is a parasitic infection that often causes hepatic cysts. Patients are frequently asymptomatic for years after infection. CT scan typically reveals a cyst with fluid, peripheral calcification, and septation. Educational objective: Hepatic adenoma is most commonly seen in young women on oral contraceptive therapy. Most cases are asymptomatic and are found incidentally on imaging for another condition. CT scan of the abdomen with contrast typically reveals a well-demarcated liver lesion with peripheral enhancement (early phase). Asymptomatic lesions <5 cm are usually managed with discontinuation of oral contraception. Symptomatic patients and patients with larger lesions should undergo surgical resection.

Question 9

A 16-year-old male comes to your office for a routine check-up.  He was diagnosed with asthma six months ago and started on inhaled corticosteroids as well as an albuterol inhaler as needed.  He reports a modest improvement in his symptoms using this regimen.  He has no complaints currently.  Physical examination reveals white plaques on his buccal mucosa that can be scraped off, leaving hyperemic spots.  The lungs are clear on auscultation.  Which of the following is the best initial therapy for the oral lesion?

Accepted Answer

Explanation: This patient's oral white plaques are typical for oral candidiasis (thrush). These plaques can typically be removed, although at times it may be difficult. A residual area of inflammation may be seen where the plaque has been removed. Most patients are asymptomatic, although some may complain of a strange, cottony taste in the mouth. The main predisposing factor in this patient is his use of inhaled corticosteroids for asthma. The patient should be observed for proper use of his inhaler, as the thrush may be a sign that he is using it improperly with a large amount of the medicine depositing in his oropharynx as opposed to passing into his lungs. A spacer device may be helpful for the patient if he is having trouble. Candida can also cause esophagitis if the infection progresses, but these patients will typically complain of pain with swallowing (odynophagia). The first-line therapy for oral candidiasis is a topical antifungal, either nystatin suspension or clotrimazole troches. Patients should also be advised to rinse their mouth after using inhaler. (Choice B) Oral fluconazole is an antifungal agent and can be used in cases that are resistant to initial treatment with topical nystatin. (Choice C) Acyclovir is used for infections caused by herpes virus, which is not likely in this patient as the white plaques are essentially diagnostic for thrush. (Choice D) Topical steroids are effective in aphthous stomatitis. However, since steroids initially led to the patient's thrush they would likely only make it worse. (Choice E) Biopsy is reserved for diagnostic dilemmas and for lesions that are concerning for malignancy. Educational objective: The best initial therapy for oral candidiasis (thrush) is a topical antifungal (e.g., nystatin suspension or clotrimazole troches), with an oral antifungal such as fluconazole used for resistant cases. In patients where thrush is secondary to inhaled corticosteroids, proper technique should be assessed by watching the patient use the inhaler.

Question 10

A 5-week-old boy is brought to the office by his mother due to vomiting.  The mother explains, "Over the past 4 days, my son has been vomiting forcefully right after drinking his formula.  He used to spit up after feeding, but it has been getting worse, and now, he seems to throw up everything he eats."  The emesis is the color of milk.  The patient has had fewer wet diapers today and a single stool yesterday.  He was born at 39 weeks gestation after an uncomplicated pregnancy.  Newborn metabolic screening was normal.  Medical history is notable for switching to formula at age 2 weeks due to low breast milk production.  At that time, the patient was at the 25th percentile for length, weight, and head circumference.  Today, he is at the 10th percentile for weight, although length and head circumference remain at the 25th percentile.  Temperature is 36.7 C (98.1 F) and pulse is 169/min.  Physical examination shows an awake, alert, slightly fussy infant.  The anterior fontanelle is open and mildly sunken.  The lips and mucous membranes are slightly dry.  Cardiopulmonary examination shows no abnormalities.  The abdomen is soft and nondistended with active bowel sounds, although waves of peristalsis are visible.  There is no hepatosplenomegaly or tenderness to palpation.  Serum chemistry is pending. 
Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf3f_2682_8f63_411476048929_MD0005_00 This young patient has findings concerning for infantile hypertrophic pyloric stenosis, a condition characterized by smooth muscle hypertrophy of the pylorus. Pyloric hypertrophy results in gastric outlet obstruction and impedes the passage of milk, resulting in the classic symptom of nonbilious, projectile emesis most commonly seen in firstborn boys age 3-6 weeks. Vomiting usually occurs immediately after oral intake, as seen in this patient, and infants classically have signs of hunger soon after. Palpation often demonstrates the hypertrophied muscle as an olive-shaped abdominal mass in the epigastrium, although its absence does not exclude the diagnosis. Visually prominent peristaltic waves may be seen and represent exaggerated gastric contractions attempting to move food beyond the obstruction. Dehydration is common, as seen in this patient with decreased urine output, a sunken fontanelle, dry mucous membranes, and a drop in weight percentiles. The diagnosis is confirmed by abdominal ultrasound, which reveals a thickened, elongated pylorus muscle. thickened, elongated pylorus muscle (Choices A and D) Gastroesophageal reflux disease is a common cause of nonbilious emesis in infants, and treatment may include proton pump inhibitor therapy and/or avoidance of milk and soy proteins (eg, hydrolyzed formula). However, symptoms are typically chronic, not acute, and most commonly consist of effortless regurgitation, not forceful vomiting. (Choice C) Increased intracranial pressure can cause projectile, nonbilious emesis and can be evaluated via ultrasonography of the head through an infant's open fontanelle. However, additional findings typically include a rapidly increasing head circumference (not seen in this patient) and a bulging, not sunken, fontanelle. Moreover, visibly prominent peristalsis suggests a gastrointestinal cause of vomiting. (Choice E) Nonbilious vomiting and poor weight gain can be presenting signs of some inborn errors of metabolism (eg, galactosemia). However, repeating negative newborn screening tests is generally of low diagnostic yield because they are highly sensitive. Because of the acute history of forceful vomiting, abdominal imaging should be prioritized; disease-specific testing for an inborn error may be considered if imaging is negative and the vomiting persists. Educational objective: Infantile hypertrophic pyloric stenosis typically presents in infants age 3-6 weeks with projectile vomiting immediately after feeding and with dehydration; visible peristalsis or a palpable, epigastric ovoid mass is common. Abdominal ultrasound is diagnostic. References: Contemporary management of pyloric stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/27521712)

Question 11

A 54-year-old man comes to the office due to a recent finding of abnormal liver function tests.  Four weeks ago, he went to the emergency department due to 2 days of diarrhea and vomiting.  During the evaluation for viral gastroenteritis, the patient was found to have elevated liver aminotransferase levels and was advised to follow up with his primary care physician.  Since then, his gastrointestinal symptoms have improved.  He has had no fever, abdominal pain, nausea, vomiting, jaundice, or pruritus.  The patient has no chronic medical problems.  He had an appendectomy during childhood with some operative complications requiring blood transfusions.  His only medication is ibuprofen as needed.  The patient does not use tobacco or illicit drugs and drinks alcohol occasionally.  He is married and in a monogamous relationship.  Temperature is 37 C (98.6 F), blood pressure is 130/80 mm Hg, and pulse is 78/min.  He has no scleral icterus, and mucous membranes are pink and moist.  Cardiopulmonary examination is unremarkable.  The abdomen is soft and nontender with no organomegaly.  Current laboratory results are as follows:  The laboratory results are discussed with the patient, and a plan for treatment with direct-acting antivirals is made.  The patient agrees to abstinence from alcohol as well as regular follow-up.  Which of the following additional interventions is most appropriate in this patient?

Accepted Answer

Explanation: This patient with elevated liver function test results has positive hepatitis C virus (HCV) antibodies and circulating HCV RNA, consistent with chronic HCV infection. Chronic HCV infection is frequently asymptomatic, and many patients have only minimal laboratory abnormalities. The mainstay of treatment is direct-acting antiviral agents (eg, sofosbuvir-velpatasvir), which have dramatically improved the ability to achieve virologic cure, but patients also require additional strategies to prevent further liver damage. A primary concern is a superimposed infection with hepatitis A virus (HAV) or hepatitis B virus (HBV), which dramatically increases the risk for rapid hepatic decompensation and liver failure. As such, patients with chronic HCV require vaccination against HAV and HBV if they do not have preexisting immunity. This patient is not immune to HAV (negative HAV antibody) and should receive HAV vaccination. He does have evidence of immunity to HBV (positive HBV surface antibody) with no suggestion of active HBV infection (negative HBV surface antigen); therefore, he does not require additional laboratory testing for HBV or vaccination against HBV (Choice E). Patients with chronic HCV infection should also receive screening for complications and comorbidities, including liver fibrosis, renal disease, and extrahepatic manifestations (eg, cryoglobulinemia). All patients should receive counseling on substance abuse and alcohol cessation. (Choice A) HCV is primarily acquired through parenteral exposure to blood with intravenous drug use or through HCV-contaminated blood transfusion. Unlike HBV or HIV, sexual contact is a rarer form of transmission; consequently, barrier protection is usually not recommended. (Choice B) Although many patients with chronic HCV infection are concerned about the use of acetaminophen, patients can generally safely take <2 g a day without adverse consequences.(Choice C) Chronic HCV infection historically was treated with interferon and ribavirin, and drug-associated depression was common. However, depression side effects are less prominent with direct-acting antiviral agents, and consequently, routine depression screening is no longer required. Educational objective: Patients with chronic hepatitis C infection may experience rapid hepatic decompensation and liver failure if they develop acute hepatitis A virus (HAV) or hepatitis B virus (HBV) infection. Consequently, in addition to alcohol avoidance, patients should be vaccinated against HAV and HBV if they do not have preexisting immunity. References: Hepatitis C: diagnosis and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/20521755)

Question 12

A 48-year-old man with alcoholic cirrhosis is brought to the emergency department due to 2 days of progressive drowsiness and lethargy.  Several months ago, the patient had similar symptoms that improved after treatment with lactulose.  He has had no nausea, vomiting, hematemesis, or melena.  The patient was diagnosed with cirrhosis a year ago and required endoscopic ligation of esophageal varices at that time.  Current medications include furosemide, spironolactone, and lactulose.  The patient has been abstinent from alcohol for the past year, takes his medications regularly, and does not use tobacco or illicit drugs.  Temperature is 37.2 C (99 F), blood pressure is 110/60 mm Hg, and pulse is 86/min.  He is somnolent but wakes up to voice and follows instructions.  Physical examination reveals mild scleral icterus, dry mucous membranes, and several spider angiomas on the upper chest.  The lungs are clear to auscultation, and heart sounds are normal with no murmur.  The abdomen is distended with shifting dullness, and there are dilated veins around the umbilicus.  No abdominal tenderness is present.  Rectal examination reveals negative occult blood stool.  A flapping tremor of both hands is present, but there are no other focal neurologic deficits.  Laboratory results are as follows:  Which of the following is the next best step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf3c_8e6e_8f63_ff8ac99ae7d2_MD0005_00 This patient with cirrhosis has altered mental status, elevated ammonia, and asterixis (flapping tremor with outstretched hands), suggesting hepatic encephalopathy (HE). HE is a spectrum of neurocognitive and motor abnormalities that primarily occurs in patients with hepatic disease. Although multifactorial in origin, most cases are due to elevated ammonia levels from a precipitating event. This patient's HE was likely precipitated by the use of diuretics for volume overload (ascites), which resulted in: Hypovolemia (dry mucous membranes, high urea nitrogen) - one of the most common precipitants of HE Hypokalemia - facilitates conversion of ammonium to ammonia Metabolic alkalosis - decreases urinary loss of ammonia He should be treated with volume and electrolyte repletion and a temporary cessation of diuretics. (Choice A) Infection is a common cause of HE in patients with hepatic disease. However, this patient has a normal leukocyte count, no fever, and no abdominal pain. Hypovolemia and electrolyte abnormalities are more likely to be the precipitants of this patient's HE. (Choice C) Lactulose is an important part of the treatment for HE, and this patient who already takes lactulose may require transient additional dosing until symptoms improve. However, the first step in treating HE is to treat the underlying precipitating cause; addressing the electrolyte and volume disturbance takes priority. (Choice D) Upper gastrointestinal bleeding is a common instigator of HE and can often be diagnosed by nasogastric lavage. However, this patient has no occult blood in his stool, no melena, and a relatively preserved hemoglobin level, making a gastrointestinal bleed less likely. (Choice E) Rifaximin is sometimes substituted for lactulose in patients whose condition does not improve within 48 hours of treatment. This patient requires correction of his electrolyte and volume abnormalities; substituting rifaximin for lactulose is not required at this time. Educational objective: Hepatic encephalopathy (HE) is usually triggered by elevated ammonia levels due to an underlying precipitating event. A common trigger of HE is excessive diuresis, which reduces intravascular volume and results in hypokalemia and metabolic alkalosis. Treatment includes volume and electrolyte repletion and using medications (eg, lactulose) to reduce ammonia levels. References: Hepatic encephalopathy in chronic liver disease: 2014 Practice Guideline by the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver. (http://www.ncbi.nlm.nih.gov/pubmed/25042402) Current concepts in the pathophysiology and management of hepatic encephalopathy. (http://www.ncbi.nlm.nih.gov/pubmed/21857820)

Question 13

A 2-year-old boy is brought to the emergency department by his grandmother due to abdominal pain and lethargy.  The grandmother reports that he was playing calmly last night when he suddenly began screaming and holding his abdomen.  The pain resolved after several minutes, but the patient has had 5 additional episodes of sudden-onset, severe pain since then.  Today, the grandmother notes that he has no interest in eating or drinking and has been "sleeping all day" but intermittently awakens in pain.  The patient has also had several episodes of nonbloody, nonbilious emesis and "fewer wet diapers than usual."  He has had no fever, diarrhea, or recent infections.  He is an otherwise healthy child with no prior hospitalizations or chronic medical conditions.  The patient takes no medications, and his immunizations are up to date.  Temperature is 37 C (98.6 F), blood pressure is 90/56 mm Hg, pulse is 160/min, and respirations are 24/min.  During the examination, the boy is sleeping and arouses briefly.  The abdomen has hypoactive bowel sounds and diffuse mild tenderness to palpation.  He is circumcised, with both testes descended and with intact cremasteric reflexes.  Immediately after the examination, the child passes blood in his diaper, as shown in the image below.  
X-ray of the abdomen reveals dilated loops of bowel and no free air.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf40_fb47_8f63_234f7ab55169_MD0005_00 This child's presentation is concerning for intussusception, which involves telescoping of a proximal portion of the intestine into a distal portion. This telescoping typically occurs due to lymphoid hyperplasia (Peyer patches) in the setting of viral infection or a pathologic lead point (eg, Meckel diverticulum). Most cases occur from age 6 months to 3 years. The most common presenting symptom is severe, intermittent, crampy abdominal pain accompanied by nonbilious emesis and drawing up of the legs to the abdomen. The classic clinical triad, seen in only 15% of patients, also includes a palpable sausage-shaped mass in the right abdomen (eg, telescoped bowel) and "currant jelly" stools (a late finding indicating bowel ischemia). When the presentation is unclear, ultrasonography is the imaging methodology of choice. The characteristic finding is a "target sign". Ultrasonography is not required in patients with a classic clinical presentation (as seen in this patient). However, radiographs of the abdomen should be considered to rule out intestinal perforation (eg, free air under the diaphragm). Radiographs may demonstrate findings of small bowel obstruction (dilated bowel loops with air-fluid levels). "target sign" After intestinal perforation has been ruled out, treatment of intussusception typically involves nonoperative reduction via air (pneumatic) or water-soluble (hydrostatic contrast) enema. These procedures allow for direct visualization of the intussuscepted bowel and are therefore both diagnostic and therapeutic. Surgical reduction is indicated if nonoperative reduction is unsuccessful. If a pathologic lead point is identified, elective surgery for removal of the lead point may be indicated. (Choice B) Barium contrast enemas were traditionally used for reduction of intussusception, but are no longer preferred given the risk of peritonitis if perforation occurs. (Choice C) Although CT scan of the abdomen can diagnose intussusception, ultrasonography is preferred given its high sensitivity and lack of associated radiation. (Choice D) A technetium-99m scan can highlight ectopic gastric mucosa within a Meckel diverticulum, which presents with painless rectal bleeding. Although Meckel diverticulum can sometimes be a lead point, hypertrophied Peyer patches are usually the nidus for intussusception. (Choice E) An upper gastrointestinal series is the radiologic test of choice to evaluate for intestinal malrotation and volvulus. Although malrotation can present with severe abdominal pain, vomiting is typically bilious. Educational objective: Intussusception occurs in children age 6 months to 3 years and presents with severe, episodic, crampy abdominal pain; emesis; and "currant jelly" stools. Air or water-soluble contrast enema is the gold standard for diagnosis and treatment of this condition. References: Intussusception in children: a clinical review. (http://www.ncbi.nlm.nih.gov/pubmed/26559998) Intussusception. (http://www.ncbi.nlm.nih.gov/pubmed/19018227)

Question 14

A 5-week-old boy is brought to the office by his mother due to vomiting.  The mother explains, "Over the past 4 days, my son has been vomiting forcefully right after drinking his formula.  He used to spit up after feeding, but it has been getting worse, and now, he seems to throw up everything he eats."  The emesis is the color of milk.  The patient has had fewer wet diapers today and a single stool yesterday.  He was born at 39 weeks gestation after an uncomplicated pregnancy.  Newborn metabolic screening was normal.  Medical history is notable for switching to formula at age 2 weeks due to low breast milk production.  At that time, the patient was at the 25th percentile for length, weight, and head circumference.  Today, he is at the 10th percentile for weight, although length and head circumference remain at the 25th percentile.  Temperature is 36.7 C (98.1 F) and pulse is 169/min.  Physical examination shows an awake, alert, slightly fussy infant.  The anterior fontanelle is open and mildly sunken.  The lips and mucous membranes are slightly dry.  Cardiopulmonary examination shows no abnormalities.  The abdomen is soft and nondistended with active bowel sounds, although waves of peristalsis are visible.  There is no hepatosplenomegaly or tenderness to palpation.  Serum chemistry is pending. Which of the following most likely represents the electrolyte profile of this patient?

Accepted Answer

Explanation: 11ec2b69_bf40_10e4_8f63_c75322f02311_MD0005_00 Pyloric stenosis causes protracted vomiting. If diagnosed early (ie, first 24-48 hr), electrolytes may be normal. In this patient with 4 days of forceful vomiting and signs of volume depletion (eg, sunken fontanelle, dry mucous membranes), electrolyte abnormalities would be expected, and hypochloremic, hypokalemic metabolic alkalosis is typical. Metabolic derangements in pyloric stenosis begin with the loss of hydrochloric acid (HCl) in the emesis, which leads to increased serum bicarbonate (HCO₃⁻) (Choice B). This results in primary metabolic alkalosis with increased serum pH (Choices C and E). In addition, loss of water and salt (more chloride [Cl⁻] is lost relative to sodium [Na⁺] due to a high gastric quantity of HCl) leads to intravascular volume depletion. loss of hydrochloric acid (HCl) Hypovolemia results in decreased renal perfusion and activation of the renin-angiotensin-aldosterone system. Aldosterone has the following effects on the kidney: It stimulates Na⁺ reabsorption (and a lesser degree of passive Cl⁻ reabsorption) to increase blood volume. The relatively greater loss of Cl⁻ compared to Na⁺ from both the stomach and kidneys leads to a large Cl⁻ deficit and characteristic hypochloremia (Choice A). It stimulates potassium (K+) secretion, leading to hypokalemia. It stimulates hydrogen (H+) secretion, exacerbating the metabolic alkalosis. Persistent hypovolemia also stimulates the appropriate secretion of antidiuretic hormone in an attempt to restore itself to euvolemia. This leads to free water retention with hyponatremia. Educational objective: Protracted vomiting, which is often seen in pyloric stenosis, characteristically causes a hypokalemic, hypochloremic metabolic alkalosis due to gastric losses and activation of the renin-angiotensin-aldosterone system. Hyponatremia also occurs and is caused by free water retention in response to hypovolemia. References: Optimizing fluid resuscitation in hypertrophic pyloric stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/26876090)

Question 15

A 62-year-old man comes to the emergency department due to periumbilical abdominal pain.  The patient says, "The pain suddenly began one hour ago and has been constant.  I never had such severe pain in my life, and nothing makes it better.  I also have nausea, and I vomited green-colored liquid once."  Two weeks ago, the patient was hospitalized after experiencing chest and epigastric pain and was diagnosed with ST elevation myocardial infarction.  He underwent percutaneous coronary intervention with stenting to the left anterior descending artery.  He has been taking dual antiplatelet therapy since then.  The patient's other medical conditions include hypertension, hyperlipidemia, and obstructive sleep apnea.  He is a former smoker with a 20-pack-year smoking history and does not use alcohol or illicit drugs.  On examination, the patient appears to be in significant pain.  Temperature is 37.2 C (99 F), blood pressure is 140/85 mm Hg, pulse is 90/min, and respirations are 22/min.  Lungs are clear to auscultation, and heart sounds are normal with no murmur.  The abdomen is nondistended and soft with mild generalized tenderness.  There is no guarding or rebound tenderness.  Bowel sounds are normal.  Stool testing for occult blood is negative.  Laboratory results are as follows:  ECG shows normal sinus rhythm with deep Q waves in the anterior leads.  Which of the following is most likely to establish the diagnosis in this patient?

Accepted Answer

Explanation: 11ec2b69_bf43_935d_8f63_61901e2784c7_MD0005_00 This older patient who recently had a myocardial infarction and now has severe abdominal pain out of proportion to his benign examination findings, along with an anion gap metabolic acidosis (Na − (HCO₃^- + Cl) = 141 − (18 + 104) = 19), should be considered to have acute mesenteric ischemia until proven otherwise. ₃^- Mesenteric ischemia occurs when the bowel does not obtain the necessary blood flow. The most common cause is superior mesenteric artery occlusion due to embolic disease; other causes include arterial and venous thrombosis due to atherosclerotic disease and watershed infarctions of areas with limited collateral vessels, generally during periods of hypotension from other causes. Patients with recent myocardial infarctions, arrhythmias, or heart failure are particularly high risk due to the ease of formation of ventricular thrombi and potential for poor perfusion. Other risk factors include hypercoagulable states and hypovolemia, including trauma or hemodialysis. Acute ischemia (similar to acute myocardial ischemia) presents as sudden-onset severe abdominal pain out of proportion to the examination findings (eg, patient has severe pain but abdominal examination shows only mild tenderness), often with nausea and vomiting; in contrast, chronic ischemia (similar to chronic angina) presents with cramping abdominal pain after eating. Patients with acute mesenteric ischemia generally do not demonstrate peritoneal signs initially on examination; they will often (but not always) have grossly bloody stool. Classic laboratory results, helpful in diagnosis, include anion gap lactic acidosis (due to intestinal cell hypoperfusion) and elevated amylase (seen in about ~50% of patients and likely reflecting intraabdominal inflammation). However, these findings are neither sensitive nor specific; therefore, normal results should not delay imaging if the diagnosis is suspected. CT angiography is the imaging modality of choice, but MR angiography can be used in patients with contrast allergy. Untreated acute mesenteric ischemia may cause bowel infarction, sepsis, and death. Mortality in this case may be as high as 60%. (Choice B) CT with oral contrast can be used in cases of suspected intestinal obstruction, which would cause a distended abdomen with hyperactive or absent bowel sounds. Oral contrast should be avoided with acute mesenteric ischemia as it can obscure the vasculature. (Choice C) Cholescintigraphy (HIDA scan) is used to evaluate for patency of the biliary tree and the presence of gallstones or cholecystitis. Cholecystitis or cholangitis would also present with abdominal pain and leukocytosis, but pain is generally located in the right upper quadrant, worsens with eating, and, in the case of cholangitis, would be associated with liver function test abnormalities and fevers. (Choice D) Acute myocardial infarction, which classically presents as left-sided pressure-like chest pain, diaphoresis, nausea, and shortness of breath, can sometimes present with abdominal pain. However, abdominal pain out of proportion to the examination findings and anion gap acidosis are more consistent with mesenteric ischemia. The patient's deep Q waves are likely due to his recent myocardial infarction. (Choice E) Esophagogastroduodenoscopy is useful for diagnosis of peptic ulcer disease (PUD), which may present with similar abdominal pain. However, PUD would not cause acidosis, anemia may be present, and stool would likely contain blood from the upper gastrointestinal tract. Educational objective: Patients with acute onset of severe abdominal pain and physical examination findings that do not match the severity of pain should be considered to have acute mesenteric ischemia until proven otherwise. The presence of metabolic acidosis further supports this diagnosis. The diagnostic test of choice is CT angiography. References: Mesenteric ischemia: Pathogenesis and challenging diagnostic and therapeutic modalities (http://www.ncbi.nlm.nih.gov/pubmed/26909235)

Question 16

A 65-year-old female with a past medical history of essential hypertension, type 2 diabetes mellitus, peripheral vascular disease, coronary artery disease, and dyslipidemia presents with epigastric pain for the past two months.  The pain is described as, "crampy, dull, and sometimes goes to the back."  The pain is worse after eating.  Four weeks of over-the-counter omeprazole did not relieve her pain.  She also complains of an 8 lb weight loss and decreased desire to eat.  Her bowel habits are normal.  She had a two-vessel coronary artery bypass surgery three years ago.  Her medications include glipizide, metformin, simvastatin, and lisinopril.  She also takes naproxen for occasional headaches as needed.  She is an ex-smoker with a 42 pack-year smoking history.  Her temperature is 36.7C (98F), blood pressure is 172/86 mm Hg, pulse is 90/min, and respirations are 16/min.  There is a right-sided carotid bruit.  Her abdomen is soft and non-tender.  Ultrasound of the abdomen shows a normal gallbladder without any stones.  An upper endoscopy shows mild esophagitis and mild antral erythema.  A CT scan of the abdomen demonstrates diffuse aortic atherosclerosis.  Screening colonoscopy done eight years ago was unremarkable.  Which of the following is the most appropriate course of action?

Accepted Answer

Explanation: This patient clearly has multiple atherosclerotic risk factors as well as known coronary artery disease and probable right carotid atherosclerotic disease given the bruit heard on physical exam. She has had a fairly extensive evaluation at this point consisting of ultrasound, CT, and endoscopy. Only mild esophagitis and gastric antral erythema have been noted thus far, which is seen in many patients and does not fully account for her pain. The key to making the diagnosis is the worsening of her dull, crampy epigastric pain after eating. Given her known atherosclerotic disease, the most likely diagnosis at this point is chronic mesenteric ischemia. The disease is sometimes referred to as "intestinal angina" since it presents as abdominal pain when there is increased oxygen demand in the bowel after eating, much as patients with cardiac ischemia experience chest pain with increased myocardial oxygen demands. The pain may become so severe that patients avoid food and consequently lose weight. Due to the large number of collateral vessels supplying the bowel, multiple high grade stenoses are typically needed in the mesenteric vasculature before patients become symptomatic. CT angiogram, MR angiogram, and duplex ultrasound are all noninvasive means of making the diagnosis. Angiography remains the gold standard for making the diagnosis, and intervention with angioplasty and/or stenting can be done in the same setting. Noninvasive tests are helpful in localizing the obstruction and to identify the best route it can be reached through with angiography. (Choice B) This patient has had a colonoscopy within the recommended screening window of 10 years and there were no findings on CT to suggest a colonic neoplasm, although this certainly does not exclude the possibility. However, chronic mesenteric ischemia is more likely at this point given the patient's symptoms and vascular disease. (Choice C) H. pylori testing was likely already done at the time of EGD. Even if it was not tested, the mild antral gastritis does not explain the current symptoms. (Choice D) This patient's symptoms appear to be related to ingestion of all foods and not just lactose. Lactose intolerance is also frequently associated with borborygmi and abnormal bulky, watery stools. (Choice E) This patient has no evidence of steatorrhea to suggest malabsorption. Educational objective: Chronic mesenteric ischemia should be considered in patients with crampy epigastric pain that worsens with meals who have had a negative initial workup. The diagnosis can be made noninvasively with CTA, MRA, or duplex ultrasound although angiography remains the gold standard test. Noninvasive tests are helpful in localizing the obstruction and to identify the best route it can be reached with angiography. References: Chronic mesenteric ischemia. Clinical presentation and diagnosis. (http://www.ncbi.nlm.nih.gov/pubmed/9146718) Multi-detector row CT angiography in patients with abdominal angina. (http://www.ncbi.nlm.nih.gov/pubmed/15256621) Chronic mesenteric ischemia. (http://www.ncbi.nlm.nih.gov/pubmed/15833694)

Question 17

A 63-year-old man comes to the emergency department due to easy fatigability and mild abdominal discomfort over the past several days.  He also has had intermittent episodes of black-colored stool but has had no chest pain, palpitations, or syncope.  His medical history is significant for hypertension, hyperlipidemia, and osteoarthritis.  The patient takes amlodipine, lisinopril, and simvastatin.  He also takes over-the-counter ibuprofen for hip and back pain that has been "acting up" over the past few weeks.  The patient does not use tobacco or illicit drugs and drinks alcohol occasionally.  Temperature is 37 C (98.6 F), blood pressure is 106/64 mm Hg supine and 100/72 mm Hg after 3 minutes of standing, and pulse is 98/min.  The patient appears pale but is otherwise in no distress.  Lung auscultation is normal.  Cardiac examination is unremarkable.  The abdomen is soft and nondistended with mild epigastric tenderness and hyperactive bowel sounds.  Rectal examination shows occult blood-positive melenic stool.  Laboratory results are as follows:  Adequate venous access is established, and intravenous crystalloids and pantoprazole are started.  Preparation for upper gastrointestinal endoscopy is made.  Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Studies show that most hemodynamically stable patients, including those with upper gastrointestinal (GI) bleeding, have better outcomes with restrictive red blood cell transfusion (eg, transfusion for a hemoglobin level <7 g/dL) than with liberal transfusion (transfusion for a hemoglobin level <9 g/dL). Restrictive transfusion may be associated with fewer complications (eg, transfusion reactions), fewer rebleeding episodes, and decreased mortality. Given his occult blood-positive melenic stools, blood urea nitrogen-to-creatinine ratio >20:1, and recent nonsteroidal anti-inflammatory drug use for hip and back pain, this patient likely has upper GI bleeding and requires proton pump inhibitor therapy and upper endoscopy. This patient is hemodynamically stable, has a hemoglobin level >7 g/dL, and has no symptoms of severe anemia (eg, chest pain, syncope); therefore, he should be closely monitored but he does not require packed blood cell transfusion. In patients with anemia, fatigue and exertional symptoms (eg, dyspnea) are not generally considered indications for transfusion. In addition, although melena indicates the presence of blood, it does not indicate active bleeding. A hemoglobin level >8 g/dL is recommended in patients with stable coronary artery disease or in those planning to undergo major surgery (eg, certain orthopedic procedures). Patients with acute coronary syndrome, severe thrombocytopenia, or cancer with a high bleeding risk may require a higher transfusion goal. Those with massive bleeding and hemodynamic instability might require blood transfusion regardless of hemoglobin levels, as initial levels may not accurately reflect the amount of blood loss (Choice D). (Choice A) Albumin infusion can be considered in the setting of spontaneous bacterial peritonitis or large-volume paracentesis. However, it has not been shown to be more effective than crystalloids for resuscitation during acute GI bleeding. (Choice C) Octreotide is recommended for upper GI bleeding due to variceal hemorrhage. This patient has no evidence of liver cirrhosis (ie, no ascites, only occasional alcohol use), making variceal bleeding less likely. (Choice E) Platelet transfusion can be considered in patients with life-threatening bleeding and platelets <50,000/mm³ or in those taking antiplatelet agents; this patient does not meet either of these criteria. Nonsteroidal anti-inflammatory drugs (eg, ibuprofen) can cause transient thrombocytopenia or platelet dysfunction, but these effects are quickly reversible. Educational objective: The threshold for blood transfusion in most stable patients with upper gastrointestinal bleeding is a hemoglobin level <7 g/dL as this is associated with fewer complications and reduced mortality. Patients with stable cardiovascular disease may benefit from maintaining a hemoglobin level >8 g/dL, and patients with acute coronary syndrome or malignancies with risk of bleeding may require higher transfusion thresholds. References: Transfusion strategies for acute upper gastrointestinal bleeding. (http://www.ncbi.nlm.nih.gov/pubmed/23281973) Restrictive vs liberal transfusion for upper gastrointestinal bleeding: a meta-analysis of randomized controlled trials. (http://www.ncbi.nlm.nih.gov/pubmed/24187470) Clinical Practice Guidelines from the AABB: red blood cell transfusion thresholds and storage. (http://www.ncbi.nlm.nih.gov/pubmed/27732721)

Question 18

A 46-year-old man is brought to the emergency department by the police after being found unresponsive on a nearby park bench.  Previously, the patient was brought to the hospital on several occasions due to acute alcohol intoxication.  No other history can be obtained.  The patient appears disheveled and has a strong smell of alcohol.  Temperature is 36.1 C (97 F), blood pressure is 110/76 mm Hg, and pulse is 84/min.  Pulse oximetry shows 98% on ambient air.  The patient does not follow instructions and withdraws all extremities to painful stimuli.  The mucous membranes are dry, and he has several spider angiomata and bilateral gynecomastia.  The lungs are clear to auscultation and heart sounds are normal with no murmur.  There is moderate abdominal distension with shifting dullness.  The liver edge cannot be palpated.  While being evaluated in the emergency department, the patient vomits a large amount of bright red blood.  Repeat vital signs show that blood pressure is 100/50 mm Hg and pulse is 110/min.  Two large-bore peripheral lines are placed and intravenous fluid is administered. 
Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: This patient has manifestations of chronic liver disease (eg, ascites, spider angiomata, gynecomastia), likely due to alcohol abuse. The large amount of hematemesis is consistent with upper gastrointestinal (GI) bleeding. Given his underlying chronic liver disease, this may be due to bleeding varices. A Mallory-Weiss tear would also be possible, given his apparent recent vomiting. Appropriate stabilization of the patient's condition should be the first step. This patient is at risk of airway compromise due to his unresponsive state (with a low Glasgow Coma Scale score) and large volume of active hematemesis, possibly leading to aspiration. Endotracheal intubation would therefore be the most important first step. Two large-bore intravenous lines should be placed to institute aggressive fluid resuscitation. A blood type and crossmatch should be sent if blood transfusion is deemed necessary. Glasgow Coma Scale After the patient's condition is appropriately stabilized, an immediate upper endoscopy would be appropriate as it is potentially both diagnostic and therapeutic (Choice D). (Choice A) Radiographic imaging is usually not necessary in the evaluation of upper GI bleeding, and a CT scan is typically not helpful as it does not easily visualize the source of bleeding. CT scan can be used in case of suspected retroperitoneal bleed. (Choice B) Given this patient's altered mental status and ascites, diagnostic paracentesis may be needed to assess for possible spontaneous bacterial peritonitis. However, this is less important than initial stabilization/resuscitation and evaluation of upper GI hemorrhage. (Choice E) Although nasogastric tubes are sometimes used to determine whether patients have ongoing bleeding, they should be avoided in patients who have varices or in whom there is a very high concern for varices (eg, alcohol use, cirrhosis). Placement can cause rupture of varices and further hemorrhage. Educational objective: Because of aspiration risk, endotracheal intubation is indicated in unresponsive patients with a large amount of hematemesis. Upper endoscopy should be performed early as it may be both diagnostic and therapeutic. References: Endotracheal intubation for airway protection during endoscopy for severe upper GI hemorrhage. (http://www.ncbi.nlm.nih.gov/pubmed/12518132)

Question 19

A 2-year-old boy is brought to the emergency department by his grandmother due to abdominal pain and lethargy.  The grandmother reports that he was playing calmly last night when he suddenly began screaming and holding his abdomen.  The pain resolved after several minutes, but the patient has had 5 additional episodes of sudden-onset, severe pain since then.  Today, the grandmother notes that he has no interest in eating or drinking and has been "sleeping all day" but intermittently awakens in pain.  The patient has also had several episodes of nonbloody, nonbilious emesis and "fewer wet diapers than usual."  He has had no fever, diarrhea, or recent infections.  He is an otherwise healthy child with no prior hospitalizations or chronic medical conditions.  The patient takes no medications, and his immunizations are up to date.  Temperature is 37 C (98.6 F), blood pressure is 90/56 mm Hg, pulse is 160/min, and respirations are 24/min.  During the examination, the boy is sleeping and arouses briefly.  The abdomen has hypoactive bowel sounds and diffuse mild tenderness to palpation.  He is circumcised, with both testes descended and with intact cremasteric reflexes.  Immediately after the examination, the child passes blood in his diaper, as shown in the image below.  The appropriate procedure is performed and the intussusception is reduced successfully.  After about an hour of rest, the patient experiences acute onset of severe abdominal pain.  Which of the following is the best next step in immediate management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf41_be99_8f63_c3b0f38d7962_MD0005_00 The resulting venous and lymphatic congestion in intussusception can cause significant intestinal edema and may result in bowel ischemia and perforation. Intestinal perforation is also the primary risk of nonoperative reduction of intussusception with therapeutic enema, although it is rare overall (<1% incidence). Children who have had symptoms for several days, those with evidence of small bowel obstruction, and those age <6 months are at greatest risk of this complication. An air (pneumatic) enema is generally preferred for initial reduction as it tends to be fast, thereby minimizing radiation exposure. In addition, perforations from air enemas tend to be smaller than from those occurring with water-soluble (hydrostatic) or barium enemas. Air, unlike other contrast mediums, is not harmful to the contents of the peritoneal cavity. Intestinal perforation results in severe abdominal pain and possible signs of peritonitis (eg, rebound, guarding). Diagnosis can be confirmed by radiographs of the abdomen in the upright or lateral decubitus positions that demonstrate the presence of free air. Treatment of intestinal perforation involves immediate surgical repair. (Choice A) Intussusception recurs in approximately 10% of patients who undergo nonoperative reduction. If recurrent intussusception is confirmed by ultrasound, repeat air enema may be indicated, but reduction should be performed only after excluding intestinal perforation. (Choice B) CT scan of the abdomen can also demonstrate the presence of free air from perforation, but plain radiographs can often be obtained more quickly and involve less radiation. (Choice C) Intravenous antibiotics are indicated in cases of intestinal perforation to cover gastrointestinal flora. However, unless the patient appears septic, antibiotics are given after the diagnosis is confirmed by imaging. (Choice E) Although ultrasound of the abdomen can demonstrate free air, radiographs are preferred and are less operator dependent than ultrasound. If no free air is demonstrated on radiography, ultrasound may be considered to evaluate for recurrent intussusception. Educational objective: Intestinal perforation is a potential complication of enema reduction of intussusception. Patients with acute pain after reduction should undergo radiographs of the abdomen to rule out intestinal perforation. References: Meta-analysis of air versus liquid enema for intussusception reduction in children. (http://www.ncbi.nlm.nih.gov/pubmed/26496576)

Question 20

A 51-year-old woman is admitted to the hospital due to a 5-day history of increasing lethargy and confusion.  The patient underwent arthroscopic knee surgery 2 weeks ago.  Acetaminophen-oxycodone was prescribed with instructions to limit total acetaminophen dosage to ≤2 g/day.  Medical history is significant for cirrhosis due to remote alcohol use disorder; she has abstained for several years.  Temperature is 36.3 C (97.3 F), blood pressure is 92/51 mm Hg, pulse is 68/min, and respirations are 24/min.  The patient is drowsy, inattentive, and unable to provide a history.  Pupils are 5 mm and reactive to light bilaterally.  Bilateral asterixis is present.  Cardiopulmonary examination is normal.  Bowel sounds are hypoactive; no fluid wave, shifting dullness, or tenderness is noted.  Abdominal ultrasonography reveals minimal peritoneal fluid; liver echotexture is nodular with no suspicious masses.  Complete blood count, renal function test results, serum electrolyte levels, and urinalysis are unremarkable.  Liver function test results include an elevated prothrombin time, decreased albumin, and elevated total bilirubin, which are unchanged from baseline results obtained before surgery.  Which of the following processes most likely precipitated the patient's current condition?

Accepted Answer

Explanation: 11ec2b69_bf3d_2aaf_8f63_2537cec7fa81_MD0005_00 This patient with cirrhosis has altered mental status. Given the bilateral asterixis and nonfocal neurologic examination, this presentation is most concerning for hepatic encephalopathy (HE). The pathogenesis of HE involves accumulation of neurotoxins (eg, ammonia [NH₃]) due to liver dysfunction. The underlying precipitants of HE usually involve disturbances in nitrogen (¹⁴N) metabolism: Increased nitrogenous waste production: infections such as spontaneous bacterial peritonitis (increased bacterial catabolism of proteins), gastrointestinal bleeding (breakdown of blood products in gut lumen), and metabolic triggers of glutaminolysis (hypokalemia, metabolic alkalosis) Decreased ammonia clearance: worsening liver function (eg, ischemia, hepatocyte loss), decreased renal function (ie, impaired NH₄⁺excretion), or constipation (eg, opioid-induced bowel slowing) New portosystemic shunting: surgically placed portocaval shunts that create a conduit for neurotoxins to bypass the liver and enter the CNS This patient's standard workup for HE (eg, serum chemistries, urinalysis, cultures) revealed no metabolic or infectious process. Therefore, other causes must be investigated. Constipation, an expected adverse effect of opioid therapy, is a common, underappreciated, and preventable HE precipitant because decreased bowel motility causes intestinal retention of nitrogen-producing bacteria. Patients lucid enough to provide a history should be asked about recent changes in stooling habits. Treatment and prevention involve bowel clearance (lactulose) and/or antibiotic therapy (rifaximin). (Choice A) Acetaminophen toxicity can cause acute hepatic necrosis, and the risk is higher with preexisting advanced liver disease and long-term heavy alcohol use. However, this patient is no longer drinking alcohol; her acetaminophen dosage of ≤2 g/day is safe, well tolerated, and a viable option for analgesia. Furthermore, her liver synthetic function (eg, coagulation profile, bilirubin, albumin) is unchanged from baseline, arguing against primary hepatic injury or deterioration as the precipitant of HE. (Choices C and D) Many opioids undergo hepatic metabolism. Decreased hepatic glucuronidation promotes accumulation of drug metabolites, which can lead to opioid toxicity (even at standard doses); by interfering with neurotransmitter signaling, opioid metabolites can depress cortical activity, thereby unmasking HE. However, opioid intoxication is classically accompanied by miosis and bradypnea (vs normal pupils and high-normal respiratory rate). (Choice E) In the circulation, many opioids are bound by plasma proteins (primarily albumin). Plasma protein-drug binding is usually decreased (rather than increased) in cirrhosis due to hypoalbuminemia. This leads to a greater fraction of unbound free drug, which can cross the blood-brain barrier to enhance CNS depression. Educational objective: Constipation should be considered as a possible cause of hepatic encephalopathy.

Exam 1: Advanced Clinical Medicine