"Not All That Fistulizes Is Crohn's Disease": A Rare Case of Ischemic Jejunocolic Fistula.

Enterocolic fistulae lead to abnormal diversion of gastrointestinal contents from the small intestine to the colon, causing diarrhea and protein energy malnutrition. We describe a rare case of a 40-year-old patient presenting with chronic diarrhea, unintentional weight loss, sitophobia, and severe abdominal pain in the setting of extensive thrombosis due to JAK2 V617F mutant disorder and associated tobacco use. Computed tomography enterography demonstrated an enterocolic fistula (jejunum to cecum), and a colonoscopy confirmed a 4 mm fistula in the cecum. The patient was nutritionally optimized with plans for a surgical fistula takedown in the future.