Deep Ulcers in the Ileum Associated with Mycophenolate Mofetil

Area of Science:

• Nephrology
• Gastroenterology
• Immunosuppression

Background:

• Renal transplantation requires long-term immunosuppression to prevent organ rejection.
• Mycophenolate mofetil (MMF) is a commonly used immunosuppressant post-transplant.
• Gastrointestinal side effects are known complications of MMF therapy.

Observation:

• A 54-year-old male renal transplant recipient developed severe diarrhea and elevated C-reactive protein (CRP) two years after starting MMF.
• Ileocolonoscopy revealed deep, punched-out ulcers in the ileum, mimicking Behçet's disease and cytomegalovirus (CMV) infection.
• Initial treatment with anti-CMV agents was ineffective.

Findings:

• The patient's symptoms and endoscopic findings were attributed to MMF-induced gastrointestinal toxicity.
• Switching immunosuppression from MMF to mizoribine led to immediate symptom improvement and CRP normalization.
• Endoscopic follow-up demonstrated complete mucosal healing six months after the switch.

Implications:

• This case highlights the importance of considering MMF-induced gastrointestinal toxicity in transplant patients with unexplained ulcerative lesions.
• Mizoribine serves as a viable alternative immunosuppressant for patients experiencing severe gastrointestinal adverse events from MMF.
• Early recognition and management of MMF toxicity can prevent significant morbidity and improve patient outcomes.