Is bronchoscopy a valuable diagnostic option for smear-negative pulmonary tuberculosis ?

Abstract

Introduction : Smear-negative pulmonary tuberculosis (SNTB) is still one of the most problematic issues of tuberculosis. Flexible bronchoscopy (FB) is the first alternative option usually used in such cases in order to collect respiratory sample. Aim of the study : To evaluate the effectiveness of FB in suspected pulmonary tuberculosis with negative sputum Methods : We have collected data from medical records of adult patients treated for a pulmonary tuberculosis (PTB) in our departement from 2006 to 2024. FB was performed in patients after two consecutive negative sputum smears for acid-fast bacilli (AFB). Patients with miliary tuberculosis pattern (known to be smear negative) were excluded. Results : Out of the 1067 patients with PTB included in our study, 182 were smear negative (17%). Among SNTB, 142 (78%) patients underwent flexible bronchoscopy. Bronchoscopic examination revealed no pathological lesions in 88 patients. The other endoscopic features were : tumor like growth (n=6), bronchial hemorrhage (n=18), hyperemia (n=22) and abnormal white granular mucosa (n=8). Bronchial aspirate smears of 78/142 patients were positive for AFB. Xpert MTB/RIF, when performed, was detected positive in 19 bronchial fluid. Bronchial biopsy provided the diagnosis in 18/91 (caseating granuloma). BK cultures in bronchial aspirate were positive in 27% of cases. <bold>Conclusion:</bold> Our study shows that SNTB is a problem that is not uncommon in clinical practice. Bronchoscopy is a valuable effective diagnostic option in this case that provides material for early diagnosis.