A 56-year-old man comes to the office for evaluation of diarrhea. He has had 6 or 7 loose, watery brown stools every day for the past 4 weeks as well as frequent nocturnal episodes while sleeping. The patient has no fever, hematochezia, melena, unexpected weight loss, or abdominal pain. He was discharged from the hospital 5 weeks ago after a protracted stay for emphysematous cholecystitis complicated by intraabdominal abscess, which required an emergency cholecystectomy and abscess drainage as well as broad-spectrum intravenous antibiotics. Medical history is significant for morbid obesity, hypertension, and hyperlipidemia. There has been no change in the patient's home medications. Temperature is 37.4 C (99.3 F), blood pressure is 145/80 mm Hg, pulse is 80/min, and respirations are 13/min. Sclera are anicteric, and mucous membranes are moist. Surgical scars on the abdomen are well healed, and the abdomen is nontender and nondistended. Laboratory results are as follows: Stool is negative for occult blood and leukocytes. Test of the stool for Clostridioides difficile toxin is negative. Erythrocyte sedimentation rate is normal. What is the most appropriate next step in management of this patient?

Question

A 56-year-old man comes to the office for evaluation of diarrhea.  He has had 6 or 7 loose, watery brown stools every day for the past 4 weeks as well as frequent nocturnal episodes while sleeping.  The patient has no fever, hematochezia, melena, unexpected weight loss, or abdominal pain.  He was discharged from the hospital 5 weeks ago after a protracted stay for emphysematous cholecystitis complicated by intraabdominal abscess, which required an emergency cholecystectomy and abscess drainage as well as broad-spectrum intravenous antibiotics.  Medical history is significant for morbid obesity, hypertension, and hyperlipidemia.  There has been no change in the patient's home medications.  Temperature is 37.4 C (99.3 F), blood pressure is 145/80 mm Hg, pulse is 80/min, and respirations are 13/min.  Sclera are anicteric, and mucous membranes are moist.  Surgical scars on the abdomen are well healed, and the abdomen is nontender and nondistended.  Laboratory results are as follows:  Stool is negative for occult blood and leukocytes.  Test of the stool for Clostridioides difficile toxin is negative.  Erythrocyte sedimentation rate is normal.  What is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d8e4_e92a_bc81_bbeebd0faa61_MD0003_00 This patient developed recurrent diarrhea that persists with fasting (nocturnal diarrhea) after undergoing a cholecystectomy. This presentation is suggestive of bile acid diarrhea (BAD), a complication that affects ~10% of patients post cholecystectomy. The gallbladder functions as a reservoir for bile acid, which is released in a controlled fashion into the small intestines to aid in fat absorption. After cholecystectomy, bile acid enters the small intestines more rapidly, which can overwhelm the resorptive capacity of the terminal ileum. Unresorbed bile acid then spills into the colon, causing mucosal irritation and secretory diarrhea. Like other causes of secretory diarrhea (eg, carcinoid syndrome), patients experience diarrhea that persists despite fasting (eg, nocturnal diarrhea). Laboratory evaluation in BAD is usually unremarkable (eg, complete blood count, erythrocyte sedimentation rate, fecal leukocytes, fecal occult blood testing). Most patients respond well to bile-acid resins, including cholestyramine, colestipol, and colesevelam, which bind bile acids and prevent colonic irritation. (Choice A) Budesonide is used to treat microscopic colitis, which also causes secretory diarrhea. However, it is much more common in women and is typically triggered by specific medications (eg, proton pump inhibitors, nonsteroidal anti-inflammatory drugs). The development of diarrhea after a cholecystectomy is more consistent with BAD. (Choice C) Lactose intolerance, which is managed with avoidance of lactose-containing foods, typically causes bloating and osmotic (postprandial) diarrhea. Fasting diarrhea is unexpected. (Choice D) Clostridioides difficile causes watery diarrhea, particularly in patients with recent hospitalizations or antibiotic use, and is treated with oral vancomycin. Although this patient was recently treated with antibiotics, fever and leukocytosis are expected. Stool antigen testing is also negative. (Choice E) Pancreatic enzyme replacement therapy is indicated for pancreatic insufficiency, which typically occurs in the setting of pancreatic resection or chronic pancreatitis (presents with chronic postprandial abdominal pain). Furthermore, pancreatic insufficiency typically causes steatorrhea (eg, bulky, foul-smelling postprandial stool). (Choice F) Sulfasalazine is used to treat ulcerative colitis, which causes diarrhea but typically also causes hematochezia, anemia, and elevated inflammatory markers (eg, erythrocyte sedimentation rate). Educational objective: Bile acid diarrhea is a common complication of cholecystectomy and occurs due to the overly rapid release of bile into the intestines, where it overwhelms the resorptive capacity of the terminal ileum and spills into the colon, resulting in secretory (fasting) diarrhea. Bile-acid binding resins (eg, cholestyramine, colestipol, colesevelam) are first-line therapy.

A 56-Year-Old Man Comes to the Office for Evaluation of Diarrhea