A 66-year-old man comes to the physician with watery diarrhea for the past 2 days. The diarrhea is nonbloody and occurs about 3 times during the day and once or twice at night. He has no fever or abdominal pain. The patient is currently on day 6 of amoxicillin/clavulanate that his primary care physician prescribed for maxillary sinusitis.
His blood pressure is 110/64 mm Hg, pulse is 84/min, and respirations are 20/min. He appears in no acute distress. Cardiopulmonary examination is within normal limits. The abdomen is soft without tenderness. Rectal examination shows normal tone without stool in the vault.

Stool samples are negative for Clostridium difficile using polymerase chain reaction.
Which of the following is the best next step in management of this patient?

Question

A 66-year-old man comes to the physician with watery diarrhea for the past 2 days.  The diarrhea is nonbloody and occurs about 3 times during the day and once or twice at night.  He has no fever or abdominal pain.  The patient is currently on day 6 of amoxicillin/clavulanate that his primary care physician prescribed for maxillary sinusitis.
His blood pressure is 110/64 mm Hg, pulse is 84/min, and respirations are 20/min.  He appears in no acute distress.  Cardiopulmonary examination is within normal limits.  The abdomen is soft without tenderness.  Rectal examination shows normal tone without stool in the vault.

Stool samples are negative for Clostridium difficile using polymerase chain reaction.
Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec193a_9815_b640_853d_8db49578c188_MD0002_00 This patient presents with acute diarrhea, defined as <14 days in duration. Acute diarrhea may be infectious or noninfectious and usually resolves spontaneously within a few days. Diagnostic evaluation is recommended for patients with severe illness such as fever >38.3 C (100.9 F), hypovolemia, bloody diarrhea, >6 stools in 24 hours or duration of illness >1 week, severe abdominal pain, recently completed course of antibiotics, or certain patient populations (eg, pregnant, elderly, immunocompromised, hospitalized). < This patient's diarrhea is most likely due to antibiotic-associated diarrhea (AAD) as he has a negative Clostridium difficile polymerase chain reaction (PCR) test and no signs of severe illness. AAD can be caused by any antibiotic but is most commonly due to clindamycin, cephalosporins, and amoxicillin-clavulanate. AAD is usually moderate in severity, lacks systemic symptoms (eg, fever, abdominal pain, fecal leukocytes), and resolves once the antibiotic is stopped. Antimotility agents may also be used to relieve symptoms. Patients with persistent diarrhea should undergo further investigation with stool studies. (Choice A) Checking stool for ova and parasites is recommended for persistent diarrhea following community waterborne illness, travel to certain geographic regions, exposure to infants in daycare centers, men who have sex with men, patients with AIDS, or bloody diarrhea with no leukocytes. (Choice B) Sigmoidoscopy is usually not required for evaluating AAD but can be helpful for differentiating between infectious diarrhea and inflammatory bowel disease and diagnosing cytomegalovirus infection in immunocompromised individuals. (Choices C and E) This patient has no fever, leukocytosis, or evidence of abdominal pain (colitis) to suggest C difficile infection. PCR tests for C difficile are very sensitive (97%) and specific (93%), and repeating the test is not recommended. Treatment with oral vancomycin also is not indicated as the C difficile PCR test is negative. Educational objective: Diarrhea is a common side effect of antibiotic therapy. Management includes checking stool for Clostridium difficile and supportive measures (eg, hydration, discontinuation of antibiotics, altering diet). Polymerase chain reaction tests for C difficile are very sensitive (97%) and specific (93%). __________ References: Antibiotic-associated diarrhea. (http://www.ncbi.nlm.nih.gov/pubmed/16610966) Probiotics for the prevention and treatment of antibiotic-associated diarrhea: a systematic review and meta-analysis. (http://www.ncbi.nlm.nih.gov/pubmed/22570464)

A 66-Year-Old Man Comes to the Physician with Watery Diarrhea