title: Diagnosis of bacterial pulmonary infections with quantitative protected catheter cultures obtained during bronchoscopy.
abstract: Quantitative bacteriology was performed on specimens collected by protected catheter fiberoptic bronchoscopy from 172 patients. Of the patients who had pneumonia, 75 of 78 (96%) had one or more species present at greater than or equal to 10(3) CFU/ml, whereas 2 of 35 (6%) control patients had organisms present in that quantity. In addition, 66% of the control specimens yielded no isolates by this technique. All of the 11 patients with bronchitis had greater than or equal to 10(3) CFU/ml. Quantitative bacteriology revealed high levels of colonization in patients without infection and endobronchial structural disease. The data suggest that bacterial counts of greater than or equal to 10(3) CFU/ml in suspended secretions collected with a protected catheter brush were diagnostic of the bacteriological etiology of lower respiratory tract infections in patients without endobronchial structural abnormalities.
mesh_terms: D001431:Bacteriological Techniques; D001980:Bronchi / Q000382:microbiology; D001991:Bronchitis / Q000382:microbiology*; D001999:Bronchoscopy; D002404:Catheterization; D003114:Colony-Forming Units Assay; D006801:Humans; D011014:Pneumonia / Q000382:microbiology*; D013183:Sputum / Q000382:microbiology