FLUTAMIDE INDUCED LUPUS

Abstract

Flutamide is an oral nonsteroidal antiandrogen used in conjunction with luteinizing hormone-releasing hormone agonists to treat stages B2 to C and D prostatic carcinoma. We describe a case of drug induced lupus caused by flutamide. To our knowledge no previous reports of flutamide induced lupus syndrome exist in the literature. CASE REPORT E. P., a 66-year-old man in whom stage C adenocarcinoma of the prostate had been diagnosed 2 years previously, presented to our hospital with fever, arthralgia, weight loss, and increasing general weakness and shortness of breath 1 month in duration. Orchiectomy had been performed 5 months after the diagnosis of adenocarcinoma. Medication consisted of 250 mg. flutamide orally 3 times daily, and iron, naproxen and amitriptyline daily. At hospital admission the patient was febrile to 38.8C. Pulmonary and neurological examinations revealed left basilar rales and proximal thigh weakness, respectively. There was no synovitis, rash or petechiae. Clinical laboratory evaluation revealed normal electrolytes, white blood count 4,200 cells per mm.3 (normal 4,500 to 11,000) and hematocrit 27.9% (normal 42 to 54). Liver function tests were normal, thyroid stimulating hormone was 4.30 mIU/ml. (normal 0.5 to 5.0) and creatine phosphokinase was 32 units per 1. (normal 24 to 195). Two months earlier and at the time of the diagnosis prostate specific antigen had been less than 0.2 and 6.9 ng./ml., respectively. Chest radiography demonstrated a left lower lobe infiltrate with small bilateral pleural effusions. The initial diagnosis was community acquired pneumonia, and treatment with a third generation cephalosporin was begun. Pleural effusion was consistent with an exudate with a negative gram stain. Bone marrow biopsy revealed early myelodysplasia. Cultures of the pleural fluid, bone marrow and blood were negative. Despite 10 days of therapy the patient remained febrile and became increasingly short of breath. Further evaluation revealed that the erythrocyte sedimentation rate was 77 mm. per hour (normal 0 to 381, the rheumatoid factor was positive at 1:40 and antinuclear antibodies were strongly positive at 1:256, while anti-histone antibody was negative. The diagnosis was lupus erythematosus. A