Mycofenolate-induced ileocolitis

Terminal ileitis is a common finding in clinical practice and is often associated with Crohn's disease. However, other pathologies must be considered particularly those resulting from side effects of drugs. We report a case of an 18-year-old female that underwent renal transplant under mycophenolate sodium, tacrolimus, and prednisolone admitted for abdominal pain, diarrhea and weight loss. Abdominal ultrasound revealed terminal ileum wall thickness, extending through 6,6 cm, while a subsequent Ileocolonoscopy revealed normal ileal mucosae but congestive cecum mucosae with superficial ulcers. Histology revealed unspecific chronic inflammation. Under the hypothesis of drug-induced enterocolitis, and after multidisciplinary discussion, mycophenolate sodium was suspended, with a rapid recovery without further treatment. This case highlights the challenge of diagnosing ileocolitis and demonstrates that MS-induced lesions can present clinical and endoscopic changes similar to those seen in Crohn's disease. Although enteric-coated MS has delayed absorption from the GI tract compared to MMF, which might reduce GI adverse events, this difference does not seem to be statistically significant.