The role of routine culture for tuberculosis during bronchoscopy in a nonendemic area: analysis of 300 cases and review of the literature.

BACKGROUND: Many centers routinely culture bronchoscopy samples for mycobacteria, even when tuberculosis (TB) is not strongly suspected. The value of this practice is poorly defined in areas with a low prevalence of TB.
METHODS: A retrospective observational study was conducted in tertiary care, university-affiliated medical center and included 300 consecutive patients who underwent a bronchoscopy examination. The findings for acid-fast bacillus (AFB) staining and culture were reviewed, and data on demographic characteristics, presenting symptoms, old TB, autoimmune status, and chest x-ray results were collected from the files.
RESULTS: The study included 175 men (58%) and 125 women, with a mean age of 62 +/- 25 years. Eight cultures (2.67%) grew mycobacteria: 4 (1.33%) Mycobacterium tuberculosis and 4 (1.33%) nontuberculous mycobacteria (NTM). Thus, the incidence of TB was 4 of 300 (1.33%) patients. There were no cases of positive AFB smear or culture in patients with atelectasis, pulmonary mass, or hemoptysis with normal chest x-ray. One of the 22 patients (5%) with diffuse pulmonary nodules had active TB as did 3 of the 134 patients (2.24%) with pulmonary infiltrates. All 4 patients with NTM had pulmonary infiltrates. The use of a cost-effective diagnostic strategy in our series, wherein testing would have been ruled out for patients without a clinical suspicion of TB and radiologic findings of a pulmonary mass (n = 107, 35.6%), would have saved the system US $5350.
CONCLUSION: The findings highlight the importance of an effective strategy for routine TB cultures during bronchoscopy in patients from nonendemic areas in whom TB is not suspected, especially those with pulmonary mass.