Azathioprine is a widely used immunosuppressant agent whose major side effect is dose-related suppression of the bone marrow, resulting in leukopenia.1 Azathioprine hypersensitivity is a very rare complication and may have a variety of manifestations (Table). Rechallenge to those patients with azathioprine can produce life-threatening results.2 We describe a patient who had not only abnormal liver function test results as well as myalgias and arthralgias owing to the use of azathioprine, but also rhabdomyolysis and an elevated serum creatinine level.
Report of a Case.
A 76-year-old man with a 10-year history of biopsy-proven pemphigus foliaceus treated with hydroxychloroquine sulfate and prednisone with poor control presented to our clinic for further treatment options. He was hospitalized secondary to significant skin involvement with multiple large erosions and occasional vesicles. The hydroxychloroquine sulfate was discontinued, and he began treatment with azathioprine, 50 mg per day orally. The azathioprine was continued at
Compton MR, Crosby DL. Rhabdomyolysis Associated With Azathioprine Hypersensitivity Syndrome. Arch Dermatol. 1996;132(10):1254-1255. doi:10.1001/archderm.1996.03890340120029