Efficacy of real-time polymerase chain reaction for rapid diagnosis of endobronchial tuberculosis

SummaryObjectivesThe definitive diagnosis of endobronchial tuberculosis (EBTB) is challenging because the disease manifests in various non-specific ways, and acid-fast bacilli (AFB) are often undetectable by sputum smear. The objective of this study was to evaluate the efficacy of real-time PCR of bronchoscopic biopsy specimens for the diagnosis of EBTB.MethodsReal-time PCR amplification of Mycobacterium tuberculosis DNA in biopsy tissue from EBTB patients was performed prospectively. Diagnostic yields were compared for real-time PCR and for auramine O-stained sputum smears and bronchial brush smears. Whether diagnostic yield depended on bronchoscopic subtype of EBTB was also evaluated.ResultsDiagnostic yields were 4.1% (3/74) for sputum smear, 39.2% (29/74) for bronchial brush smear, and 89.2% (66/74) for real-time PCR. Real-time PCR melting curve analysis showed significantly higher yields than did AFB staining of bronchial brush smears for granular and caseating EBTB (p