A 36-year-old woman with gallbladder disease had an incidental finding of asymptomatic cavitary lung infection with Blastomyces dermatitidis. No treatment was given initially, and 2 months later she presented with vertebral osteomyelitis, paraspinal abscess, and spinal cord compression due to dissemination of the fungus. The patient recovered following surgical debridement and treatment with 1 g of amphotericin B, followed by itraconazole 400 mg QD for 6 months. In spite of previous reports of the self limiting nature of primary pulmonary blastomycosis in the normal host, antifungal therapy may be needed in cases that do not resolve spontaneously within a short period of time, or if transient immunosuppression may be anticipated as may occur following surgery or after acquisition of other infections.