Wegener's granulomatosis: observations on treatment with antimicrobial agents.

Twelve patients with Wegener's granulomatosis were treated with antimicrobial agents, chiefly trimethoprim-sulfamethoxazole. The clinical course improved in 11 of the 12 patients who received this treatment. The success of antimicrobial treatment suggests the possibility of a microbial infection as the inciting cause of Wegener's granulomatosis in some patients. Alternatively, these agents--in particular, trimethoprim-sulfamethoxazole--may possess immunosuppressant activity.