The tolerability of newer immunosuppressive medications in a patient with acute intermittent porphyria

Acute intermittent porphyria results from a deficiency of the porphobilinog en deaminase enzyme of heme biosynthesis and is commonly exacerbated by a w ide variety of medications. When referred a patient with acute intermittent porphyria for a renal transplant, only steroids and azathioprine were disc overed as safe in patients with acute intermittent porphyria. The administr ation of many newer immunosuppressive medications, including calcineurin in hibitors, has nor been documented in acute intermittent porphyria. Actually , cyclosporine is presently considered contraindicated in acute intermitten t porphyria. To determine if calcineurin inhibitors would be tolerated in a cute intermittent porphyria, cyclosporine and tacrolimus Mere administered pretransplant and were documented not to exacerbate acute intermittent porp hyria. A successful renal transplant was then performed using tacrolimus. T his is the first reported patient with documented acute intermittent porphy ria to tolerate safely several of the newer immunosuppressive medications, including tacrolimus, mycophenolate, and rabbit antithymocytic globulin fol lowing renal transplantation. This patient's pretransplant evaluation also suggested that cyclosporine may be safe for some patients with acute interm ittent porphyria. Journal of Clinical Pharmacology; 2001;41:113-115 (C) 200 1 the American College of Clinical Pharmacology.