Is ferritin level elevated in SIBO? How does linoclotide work? How would you prevent Montezuma’s Revenge? Try these 3 case challenges.
Colonic Motility Dysfunction: A 3-case GI Challenge
Case #1. A 28-year-old woman presents with postprandial diarrhea and bloating. Which of the laboratory abnormalities above is most likely to be present in this patient?
Answer: D. Decreased serum vitamin B12. Small intestinal bacterial overgrowth (SIBO) can occur in cases of surgically altered gastrointestinal anatomy, diabetes mellitus, and several other predisposing conditions.
#2. A 39-year-old woman presents for evaluation of chronic constipation. You make the shared decision to start linaclotide. Which of above is the mechanism of action for this medication?
Answer: D. Guanylate cyclase-C agonist. Linaclotide works as an agonist at the guanylate cyclase-C receptor, resulting in increased colonic water and assisting with transit.
#3. An otherwise healthy 25-year-old man presents for evaluation prior to a trip to rural West Africa. Data to support prevention of traveler’s diarrhea when the drug is taken daily is strongest for which of the above?
Answer: C. Rifaximin. Rifaximin has been shown to reduce the incidence of traveler’s diarrhea if taken once-a-day during a trip and continued for an additional 2 days after the travel is complete.
