Unusually late-onset mycophenolate mofetil-related colitis.

PURPOSE

Serious gastrointestinal complications arising 13 years after the initiation of posttransplant immunosuppressant therapy with mycophenolate mofetil are reported.

SUMMARY

Over a three-month period, a male heart transplant recipient who had taken oral mycophenolate mofetil (2 g daily) for 13 years as part of an immunosuppressant maintenance regimen developed diarrhea and weight loss leading to renal failure and metabolic acidosis. There was no evidence of opportunistic infection, and immunostaining for cytomegalovirus yielded negative results. Colonoscopy revealed areas of congested, erythematous, and nodular mucosa. Histological examination of mucosal biopsy specimens revealed pathological abnormalities typical of those seen in cases of mycophenolate mofetil-associated colitis. On discontinuation of mycophenolate mofetil use, the patient's diarrhea resolved and his renal function improved. Colitis, diarrhea, and other gastrointestinal complications are commonly reported in patients receiving mycophenolate mofetil, an immunosuppressant widely used to prevent rejection of solid organ or bone marrow transplants; however, the onset of such symptoms after more than a decade of continuous use of the drug has not been previously reported. This case suggests that mycophenolate mofetil toxicity should be considered in the evaluation of late-onset posttransplant diarrhea regardless of the duration of therapy.

CONCLUSION

A 33-year-old man maintained on mycophenolate mofetil for 13 years after heart transplantation developed diarrhea, weight loss, and acute kidney injury over a three-month period. Colonoscopy and biopsy revealed pathological changes consistent with mycophenolate mofetil toxicity, and the patient's symptoms resolved after the drug was discontinued.