A model for performing fiberoptic bronchoscopy as a supplement to noninvasive diagnostic methods, in patients with community-acquired pneumonia, was prospectively studied. Twenty-four patients underwent bronchoscopy, seven pilot patients and 17 of 277 (6 percent) consecutive patients with CAP. Indications for FOB were early therapy failure (less than or equal to 72h)(n = 7), late therapy failure (greater than 72h)(n = 11), or before start of antibiotic therapy in severely ill or immunocompromised patients (n = 6). Samples were obtained by aspiration of bronchial secretion and with a protected brush catheter from which quantitative cultures with a detection level of 10(4) colony forming units per ml were performed. Results concluded that FOB, with the use of quantitative PB-cultures, offered a safe and specific diagnostic tool, which on special indications, can be of great value in the management of patients with CAP.