Diffuse colitis during mycophenolate mofetil treatment: a case report.

Mycophenolate mofetil (MMF) or Cellcept(R) is a potent immunosuppressor tha t inhibits purin synthesis used to prevent human allograft rejection. The m ost important secondary effects include haematological and intestinal disor ders. Among them, diarrhea is the most common. It is dose-dependant and app ears commonly during the first 2 months of treatment. Its physiopathology r emains unclear. We reported a case of colitis, 6 months after a kidney tran splantation. The patient was treated since day 2 with 2 grams per day of MM F. Morphological analysis showed a diffuse colitis from the coecum to the r ectum. Histological samples confirmed a colitis with atrophic crypts but wi th mucosal secretions and same cryptic abscesses. No granuloma or CMV inclu sion was founded. Histochemical immunostaining for CMV was negative. Finall y, symptoms regressed within 5 days after tapering down MMF dose in associa tion with metronidazole treatment. The role of MMF in inducing colitis is d iscussed.