Gyrus Daily Questions; Internal Medicine #42

[cingulate.gyrus]

A 24-year-old woman with a history of irritable bowel syndrome (IBS) has been treated with loperamide, psyllium, and imipramine. Because of continued abdom-inal pain, bloating, and alternating constipation/diarrhea, she is started on alosetron, 0.5 mg bid. Five days later she is brought to the emergency department with severe ab-dominal pain. On examination she is in severe discom-fort. Her temperature is 39°C, blood pressure 90/55 mmHg, heart rate 115 beats/min, respiratory rate 22 breaths/min, and oxygen saturation normal. Abdominal examination is notable for hypoactive bowel sounds, dif-fuse tenderness, and guarding without rebound tender-ness. Her stool is heme positive. Laboratory studies are notable for a white blood cell count of 15,800 with a left shift and a slight anion gap metabolic acidosis. Which of the following is the most likely diagnosis?


A. Appendicitis
B. Clostridium difficile colitis
C. Crohn’s disease
D. Ischemic colitis
E. Perforated duodenal ulcer

[MANIAKOS]

dont really know...a?

[K06100]

D. Ischemic colitis

[Novobiocin]

D. Ischemic colitis

Alosetron was withdrawn from the market in 2000 owing to the occurrence of serious life-threatening gastrointestinal adverse effects, but was reintroduced in 2002 with availability and use restricted.The cumulative incidence of ischaemic colitis was 2 in 1000, while serious complications arising from constipation (obstruction, perforation, impaction, toxic megacolon, secondary colonic ischaemia, death) was 1 in 1000.[4]

[cingulate.gyrus]

The answer is D.Ischemic colitis

Serotonin receptor antagonists enhance the sensitivity of the afferent neurons projecting from the gut. Alosetron, a 5-HT3 receptor antagonist, reduces perception of painful visceral stimulation, induces rectal relaxation, and delays colonic transport in patients with IBS.

Clinical studies have shown the long-term efficacy of alosetron for IBS. However, in postrelease surveillance, 84 cases of ischemic colitis were
reported soon after patients were placed on alosetron. Of these, 44 cases required surgery and 4 patients died. Most cases developed within 30 days of starting the medication, and many were within 1 week. Alosetron was withdrawn voluntarily in 2000 but has been reintroduced with a strict monitoring program. Given the temporal relation and compatible clinical presentation, that is the most likely diagnosis in this case.

A CT scan would likely show diffuse colitis. Therapy involves discontinuation of the drug, supportive therapy, and possible surgical resection. The other diagnoses may present with a similar clinical picture and should be on the differential diagnosis.