S1790 Severe Pancolitis: The Battle Between Medications and Ischemia

Abstract

Introduction: Mycophenolate Mofetil (MMF) is an essential drug in the treatment of solid organ transplant recipients (SOTRs) to maintain immunosuppression. Gastrointestinal side effects such as vomiting and diarrhea are common manifestations of its use; however, MMF-induced pancolitis with endoscopic findings of ischemic injury is an uncommon presentation. We illustrate a case of severe pancolitis secondary to chronic MMF use. Case Description/Methods: A 66-year-old female with a history of hepatitis C and hepatocellular cancer status post orthotopic liver transplant in 2015 presented to the emergency room with a 2-day history of nausea, diarrhea, and severe abdominal pain. There was no blood or mucous in her stool. Home medications included MMF 500mg twice daily and cyclosporine 75mg twice daily. Vitals showed a temperature of 37.4°C, pulse of 104 bpm, and normotension. Examination showed diffuse abdominal tenderness without rigidity or guarding. Labs significant for a mild leukocytosis. Stool cultures and Clostridium difficile testing were negative. A CT scan of the abdomen revealed pancolitis with diffuse colonic wall thickening and adjacent stranding. Subsequent sigmoidoscopy revealed severe stenosis with abnormal, friable, grey mucosa in the rectosigmoid colon that could not be traversed (Figure 1). Given concern for ischemia, CT angiography was performed and there was patency throughout the superior mesenteric artery, inferior mesenteric artery, and their branches. Histopathology results from the sigmoidoscopy was negative for cytomegalovirus and herpes simplex virus, but it did reveal chronic colitis with fibrin thrombi likely related to chronic ischemia versus drug-induced injury. Given the lack of prior prodromal illness, negative infectious workup, and no evidence of vessel occlusion, a diagnosis of MMF-induced pancolitis was made. MMF was discontinued and her symptoms improved with supportive care. Follow-up colonoscopy as an outpatient several weeks later demonstrated healing colitis. Discussion: MMF remains a mainstay in SOTRs, but gastrointestinal (GI) side effects such as nausea, vomiting, diarrhea, and abdominal pain remain prevalent. About a half of patients have normal colonoscopy evaluations, with colitis-like characteristics being the most common histologic finding. However, our patient had severe stenosis complicated by ischemic injury, which is an uncommon pattern. Clinicians should keep this diagnosis in their differential for patients on MMF who have persistent GI symptoms.Figure 1.: A) CT scan showing pancolitis with wall thickening. B) Sigmoidoscopy showed stenosis and abnormal mucosa in rectosigmoid colon.