In a 21-year-old male patient afflicted with widespread recurrent pyoderma resistent to antimicrobial therapy since 3 years, a deficient state of cellular immunity including dysfunctions of both microphages and T lymphocytes was disclosed. After 6 weeks of systemic treatment with levamisole all lesions cleared completely, whereas appropriate long-term antibiotic therapy previously administered had failed to succeed. The immunological parameters, as far as being reexamined, also returned to normal levels during levamisole therapy.