Sumatriptan-Associated Ischemic Colitis (IC)

Abstract

Results: A 50 yr WF was admitted at 3 pm for abdominal pain, nausea, vomiting and bloody diarrhea. She awoke at 3 am with LLQ pain, diaphoresis and tenesmus, and subsequently had 6 bowel movements which progressively became more bloody. The pain was continuous, crampy, non-radiating with pain 8/10, requiring narcotics. She denied GI symptoms like this in the past. She has a PMH of migraine and had been using sumatriptan tablets for about 15 yrs, usually once every other month. She had not used the IM form until 8 days prior to the onset of these symptoms, a one time 6 mg injection. On abdominal exam, she was tender in the LLQ without guarding or rebound; bowel sounds were hyperactive. The rest of her physical exam was normal. WBC was 16,700 with 92% neutrophils. A colonoscopy performed the next morning showed a normal rectum and sigmoid colon. In the upper descending colon, a colonic “stripe sign” (an area of broad exudate) was noted, beyond which were changes of severe colitis consistent with ischemia at the splenic flexure. Bx was consistent with acute IC. An IC scoring system (developed for IC cases associated with alosetron-Ringle et al Gastroenterology 2005;128 (No 4 suppl 2):A-467) gave a score of 15 out of 17, indicating a very high probability of IC. She was started on mesalamine, pentoxyfylline, Cipro, and metronidazole. Stool studies were negative. An MRI/MRA was consistent with IC, with edema and colonic wall thickening from the hepatic felxure to distal sigmoid colon, with no vascular abnormalities. A 2-D echo was normal with an EF of 60% and no thrombus. Over the next few days her pain and nausea diminished, she tolerated a regular diet, and her WBC normalized and was discharged. A repeat colonoscopy 6 weeks later showed complete healing of the mucosa, with some residual scarring at the splenic flexure. The rest of the colon, including the terminal ileum, was normal. There have been only two previous reports of IC caused by sumatriptan; one being a case report and the 2nd a series of 7 cases reported to the FDA. In our pt, despite having used oral sumatriptan for years, her presentation after the IM form was classic for IC. No other causes were found Conclusion:Figure: severe ischemic colitis changes characterized by purplish mucosa, exudates, and friability.