Role of Induced Sputum, Bronchial Aspirate and Post Bronchoscopic Sputum in the Diagnosis of Sputum Smear Negative Pulmonary Tuberculosis.

ABSTRACT

Background: The diagnosis of Pulmonary Tuberculosis is largely dependent of the positive result of the sputum smear by ZN staining. But in many cases, although active tuberculosis is present, due to many reasons, sputum smear may yield a negative result. With a late culture result, no reliable serological test available to enable an early diagnosis, role of induced sputum and bronchoscopy has been tried with excellent results. Methods: 50 fresh smear negative cases between the ages of 16-65 years, clinically and radiologically suspected of Pulmonary Tuberculosis were subjected to induced sputum and bronchoscopy after detailed history and thorough clinical examination as done. Clinical symptoms were noted, 2 sputum smears (spot and early morning) and chest x-rays were taken for all patients. Results: Males between 24 – 44 years were seen to be predominant patients. The most common symptom appeared to be cough in 80% followed by fever in 60% of the cases. 76% of patients had unilateral lesions and 24% with bilateral lesions. 84% of the sputum negative patents were identified as active tuberculosis cases. Conclusion: Induced sputum and fiber optic bronchoscopy with bronchial aspirate and post bronchoscopic sputum can provide excellent material for diagnosis of suspected cases of Pulmonary Tuberculosis in whom smears of expectorated sputum do not reveal mycobacteria. There is minimum patient discomfort, reduced complications and relatively good yield which makes these procedures justifiable in the diagnosis of fresh smear negative pulmonary tuberculosis.