Red blood cell anemia in a patient with pemphigus vulgaris induced by the use of mycophenolate mofetil and prednisone.

Mycophenolate mofetil (MMF) is an immunosuppressive drug used in renal transplantation, lupus nephritis and pemphigus vulgaris patients. An apparent link is described between the use of MMF with prednisone to treat pemphigus vulgaris and the development of red blood cell anemia. Specifically, after initiation of 500 mg MMF twice a day given in conjunction with the long-standing use of prednisone, which had been tapered to a dose of 10 mg daily, the patient's red blood cell count dropped by 17% over 7 weeks. To put this into perspective, total aplasia of red blood cells for 40 days would result in a drop of 30-33% in the red blood cell count. In the transplantation literature, MMF has been noted to lower red blood cell counts. One previous study of four transplant patients whose immediate post-transplantation immunosuppression utilized corticosteroids, cyclosporine, MMF, and anti-T-lymphocyte globulin noted anemia in 13% of them. The dermatology literature heretofore has not noted that anemia is a side effect of patients taking MMF to treat pemphigus. This report suggests that anemia can occur due to MMF, in particular when it is given with prednisone, a side effect well documented in the transplantation literature when the triple combination of MMF, cyclosporine and prednisone is used. It would therefore seem prudent to monitor red and white blood cell counts in patients taking MMF. A review of the literature also reveals that MMF is a safe medication that appears to have a more favorable side effect profile than azathioprine, although it is more expensive than azathioprine.