The results of this study demonstrate that quantitative BAL cultures are as reliable as TPC cultures in diagnosing etiology of CAP
Few studies have examined the diagnostic value of bronchoscopic techniques in patients with CAP. Sorensen et al studied 36 patients with severe CAP and performed a very thorough diagnostic study that included bronchoscopy with TPC. Although bronchoscopic tests were performed in patients receiving antibiotics, the authors were able to establish an etiologic diagnosis in 29 (81 percent) cases. TPC and BAL cultures gave 48 percent (14/29) and 38 percent (8/21) positive results, respectively. Since quantitative cultures were not performed, it is difficult to correctly address these data. Although S pneumoniae caused pneumonia in 12 cases, only 3/7 TPC and 1/7 BAL samples obtained from these patients yielded S pneumoniae. It is possible that these results were influenced by previous antibiotic treatment.
In another investigation, Ortqvist et al° studied 24 CAP patients with fiberoptic bronchoscopy and TPC cultures for obtaining an etiologic diagnosis. Altogether, the authors could establish an etiologic diagnosis in 79 percent (19/22) of patients. The study included only six patients without previous antibiotic therapy and in four of them the etiology was established with TPC.