Late dissemination of pulmonary blastomycosis during ketoconazole therapy

We report a patient with pulmonary blastomycosis who suffered relapse with dissemination of her disease after five months of apparent response to therapy with ketoconazole, 400 mg daily. Common causes of drug failure, including noncompliance and failure of absorption, were excluded, and there was no evidence of altered host immunity. Previous reports of relapse during and after ketoconazole therapy are reviewed; no previous case was found with recurrence near the end of a six-month period of apparently effective therapy. Close followup during the entire course of ketoconazole therapy for blastomycosis and following its completion is recommended.