Role of Bronchoalveolar Lavage in Sputum-Smear Negative, Clinically and Radiologically Suspected New Cases of Pulmonary Tuberculosis

Dr Mathew Varghese; Dr Mahendra Kumar Bainara

Volume : VIII, Issue : VII, July - 2019

Role of Bronchoalveolar Lavage in Sputum-Smear Negative, Clinically and Radiologically Suspected New Cases of Pulmonary Tuberculosis

Dr Mathew Varghese, Dr Mahendra Kumar Bainara

Abstract :

Background – Only 50 to 60% of PTB cases are found to be sputum–smear positive. Diagnosis without bacteriological confirmation can lead to either under or over diagnosis. This study was conducted to investigate on the usefulness of BAL for the early diagnosis of new sputum–smear negative PTB cases. Objective – To evaluate the diagnostic yield of BAL in the microbiological confirmation of AFB in new sputum–smear negative, clinically and radiologically suspected new cases of PTB. Materials and Methods – 72 PTB suspected sputum–smear negative patients were subjected to FOB, and BAL samples were sent for Zeihl–Neelson staining, culture on L–J slants, and CBNAAT. The data was statistically analyzed (Graphpad Instat). Results – The diagnostic yields of BAL microscopy, BAL CBNAAT and BAL culture were found to be 43.05%, 54.17% and 55.56% respectively. Diagnostic yield when all the three investigations were combined was 58.33%. On compå with the BAL culture results the sensitivity, specificity, PPV & NPV of BAL microscopy and BAL CBNAAT were found to be 72.5%, 93.75%, 93.55% & 73.17% and 95%, 96.88%, 97.44% & 93.94% respectively. Conclusion – BAL has a significant role in the early diagnosis of sputum–smear negative PTB. CBNAAT is more sensitive and specific compared to microscopy, and rapid compared to culture method.