Malabsorption syndromes — MCQs

A 21-year-old woman comes to the physician because of a 2-month history of fatigue, intermittent abdominal pain, and bulky, foul-smelling diarrhea. She has had a 4-kg (8-lb 12-oz) weight loss during this period despite no changes in appetite. Examination of the abdomen shows no abnormalities. Staining of the stool with Sudan III stain shows a large number of red droplets. Which of the following is the most likely underlying cause of this patient’s symptoms?

A 28-year-old man presents to his primary care provider complaining of intermittent stomach pain, non-bloody diarrhea, and weight loss for the last 3 months. He has occasional abdominal pain and fever. This condition makes studying difficult. He has tried omeprazole and dietary changes with no improvement. Past medical history is significant for occasional pain in the wrists and knees for several years. He takes ibuprofen for pain relief. His temperature is 38°C (100.4°F). On mental status examination, short-term memory is impaired. Attention and concentration are reduced. Examination shows no abnormalities or tenderness of the wrists or knees. There are no abnormalities on heart and lung examinations. Abdominal examination is normal. Upper endoscopy shows normal stomach mucosa but in the duodenum, there is pale yellow mucosa with erythema and ulcerations. Biopsies show infiltration of the lamina propria with periodic acid-Schiff (PAS)-positive macrophages. Which of the following best explains these findings?

A 23-year-old man presents to the office complaining of weight loss and fatigue for the past 2 months. He states that he has been experiencing foul-smelling, light-colored stools but thinks it is because he hasn’t been eating well, recently. He has a past medical history significant for cystic fibrosis, which is well-controlled medically. He denies any shortness of breath, chest or abdominal pain, nausea, vomiting, or melena. On physical examination, his skin is pale and dry. Which of the following would be the most likely etiology of a malabsorption syndrome giving rise to this patient’s current condition?

A 15-year-old girl is brought to the physician because of an 8-month history of fatigue, intermittent postprandial abdominal bloating and discomfort, foul-smelling, watery diarrhea, and a 7-kg (15-lb) weight loss. She developed a pruritic rash on her knees 3 days ago. Physical examination shows several tense, excoriated vesicles on the knees bilaterally. The abdomen is soft and nontender. Her hemoglobin concentration is 8.2 g/dL and mean corpuscular volume is 76 μm3. Further evaluation of this patient is most likely to show which of the following findings?

A 29-year-old man presents to clinic with a complaint of fatigue that has developed over the past 6 months. Upon questioning, he endorses abdominal pain, non-bloody diarrhea, and decreased appetite over the past year. He denies recent travel outside of the country or eating uncooked meats. On exam, his temperature is 99.0°F (37.2°C), blood pressure is 126/78 mmHg, pulse is 93/min, and respirations are 12/min. Notably, the abdominal exam is unremarkable aside from some tenderness to palpation near the umbilicus. His colonoscopy demonstrates perianal inflammation with a normal rectum, and biopsies of suspicious lesions in the transverse colon reveal transmural inflammation. Which one of the following is most strongly associated with the patient’s condition?

A 19-year-old woman with a known history of malabsorption presents with a painful red tongue, red eyes, and cracked lips. She says her symptoms gradually began 4 months ago after moving away from home for college. She also complains of photophobia, spontaneous lacrimation, and itchy dermatitis. Past medical history is significant for a long-standing malabsorption syndrome, which she says that she hasn't been able to maintain her normal diet or take her vitamins regularly due to her busy schedule. The patient is afebrile and vital signs are within normal limits. On physical examination, she has a malnourished appearance with significant pallor. Conjunctival injection is present bilaterally. Which of the following diagnostic tests will be most helpful to support the diagnosis of the most likely vitamin deficiency in this patient?

A 54-year-old man comes to the physician because of diarrhea that has become progressively worse over the past 4 months. He currently has 4–6 episodes of foul-smelling stools per day. Over the past 3 months, he has had fatigue and a 5-kg (11-lb) weight loss. He returned from Bangladesh 6 months ago after a year-long business assignment. He has osteoarthritis and hypertension. Current medications include amlodipine and naproxen. He appears pale and malnourished. His temperature is 37.3°C (99.1°F), pulse is 76/min, and blood pressure is 140/86 mm Hg. Examination shows pale conjunctivae and dry mucous membranes. Angular stomatitis and glossitis are present. The abdomen is distended but soft and nontender. Rectal examination shows no abnormalities. Laboratory studies show: Hemoglobin 8.9 g/dL Leukocyte count 4100/mm3 Platelet count 160,000/mm3 Mean corpuscular volume 110 μm3 Serum Na+ 133 mEq/L Cl- 98 mEq/l K+ 3.3 mEq/L Creatinine 1.1 mg/dL IgA 250 mg/dL Anti-tissue transglutaminase, IgA negative Stool culture and studies for ova and parasites are negative. Test of the stool for occult blood is negative. Fecal fat content is 22 g/day (N < 7). Fecal lactoferrin is negative and elastase is within normal limits. Which of the following is the most appropriate next step in diagnosis?

A 42-year-old woman presents with exertional dyspnea and fatigue for the past 3 months. Her past medical history is significant for multiple episodes of mild diarrhea for many years, which was earlier diagnosed as irritable bowel syndrome (IBS). She denies any current significant gastrointestinal symptoms. The patient is afebrile and vital signs are within normal limits. Physical examination reveals oral aphthous ulcers and mild conjunctival pallor. Abdominal examination is unremarkable. There is a rash present on the peripheral extremities bilaterally (see image). Laboratory findings are significant for evidence of microcytic hypochromic anemia. FOBT is negative. Which of the following is the most likely diagnosis in this patient?

A previously healthy 20-year-old woman comes to the physician because of recurrent abdominal cramps, bloating, and diarrhea for 4 months. She describes her stools as greasy, foul-smelling, and difficult to flush. During this time she has had a 6-kg (13.2-lb) weight loss. She has no personal or family history of serious illness. Physical examination shows pallor and cheilitis. Laboratory studies show a hemoglobin concentration of 11 g/dL. Serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. Test of the stool for occult blood is negative and stool microscopy reveals no pathogens and no leukocytes. Analysis of a 24-hour stool sample shows 12 g of fat. The patient is asked to consume 25 g of d-xylose. Five hours later, its concentration is measured in urine at 2 g (N = > 4 g/5 h). The test is repeated after a two-week course of rifaximin, but the urinary concentration of d-xylose remains the same. Which of the following is the most likely diagnosis?

A 34-year-old man presents with dysphagia. The patient says that he has pain on swallowing which gradually onset 2 weeks ago and has not improved. He denies any change in diet but does say that he recently returned from a prolonged work trip to the Caribbean. No significant past medical history or current medications. On physical examination, the patient looks pale. His tongue is swollen and has a beefy, red appearance. Angular stomatitis is present. Laboratory findings are significant for macrocytic, megaloblastic anemia, decreased serum folate, increased serum homocysteine, and normal methylmalonic acid levels. Which of the following conditions most likely caused this patient’s symptoms?