Among 169 patients treated for superficial bladder tumors with intravesical instillations of 150 mg BCG-Pasteur, five developed BCG-itis--a severe systemic infection with bronchopulmonary lesions and granulomatous hepatitis. In four cases, the complication appeared early during treatment (after three, six, six and eight instillations respectively). In one case, BCG-itis appeared 6 months after completion of 2 years monthly maintenance therapy. In addition to pulmonary basal infiltration and granulomatous hepatitis, intramedullary granulomatosis was observed. In three patients, the role of trauma has to be considered, as BCG-itis appeared after a traumatic instillation with bleeding. All patients were cured by combined treatment with Rifampicin, Isoniazid and Prednisolone.