Egyptian Journal of Medical Microbiology, January 2006 Vol. 15, No 1 177 Induced Sputum Versus Fiberoptic Bronchoscopy in The Diagnosis of Pulmonary Tuberculosis Amr A. Darwish, Ahmed A. Ali, Wafaa A. Zahran*, Nourane Y. Azab and Mohammed A. Agha Chest & Microbiology and Lmmunology* Departments Faculty of Medicine, Menoufiya University Tuberculosis still constitutes a major health problem despite advances in diagnosis and treatment. The diagnosis of TB is difficult in patients who cannot produce sputum spontaneously. This study aimed to compare between sputum induction using nebulized hypertonic saline, and fiberoptic bronchoscopy in the diagnosis of pulmonary TB, in clinically and radiologically suspected cases. Methods: Thirty suspected pulmonary tuberculosis cases were subjected to: 1-Tuberculin skin test. 2-Sample collection: a. Three successive spontaneous morning sputum samples, b. Sputum induction for 3 successive mornings c. Fiberoptic bronchoscopy with bronchial washing, brushing & Post-bronchoscopic sputum collection. All samples were stained with Ziehl-Neelsen stain. Induced sputum (SI) and bronchial wash were also cultured on Lowenstein-Jensen (L.J) medium. Results: According to L J cultures there were 25(83.3%) positive bronchial wash samples VS 22(73.3%) induced sputum samples. The diagnostic yields of sputum induction and post-bronchoscopic sputum were similarly significant. Also, the yields of bronchial washing and bronchial brushing were similarly highly significant .The differences between all these procedures was non significant. The third SI sample was the most sensitive in the detection of AFB There was no significant difference between SI & Bronchial washing whether by using Z-N stain or L-J culture. Sensitivity, specificity and predictive values of different methods of specimen collection in diagnosing pulmonary TB gave non-significantly different results. Conclusion: Sputum induction is an easy, cheap and non invasive procedure that has a significantly high diagnostic yield for clinically and radiologically suspected cases of pulmonary tuberculosis who have dry cough or whose sputum for three successive days are negative. The third SI sample is the most significant one. There is no significant difference between SI and FOB using any of its procedures INTRODUCTION Tuberculosis had coexisted with humanity before recorded history. In spite of the major advances in the diagnosis, treatment and prevention of TB, it remains one of the major public health problems worldwide, with 95% of cases and 98%of deaths occurring in developing countries (1) . In Egypt, TB is the second most important health problem after bilharziasis. (2) The continuous threat of TB had lead to an urgent need for effective diagnostic procedures (3) . The clinical diagnosis of pulmonary tuberculosis is quite variable & its radiological diagnosis is only suggestive, so the identification of organisms is so critical. (3) Culture remains the gold standard method for the diagnosis of MTB, nevertheless several nucleic acid based techniques have been developed for its diagnosis (4) .Mycobacterial culture is much more sensitive than microscopy, being able to detect as few as 10 bacteria/ml of material. (3) For more than 3 decades, sputum induction (SI) has been widely used as a non-invasive tool for the diagnosis of tuberculosis (5). .Sputum induction helps to wash off mucous from the bronchial tree and its hypertonicity irritates and induces osmotic transudation of fluid across the bronchial tree membrane (5). . However, with the advent of fiberoptic bronchoscopy (FOB), sputum induction was largely abandoned. Recently, it has enjoyed a modest revival because of its safety, and much lower costs (6). The fiberoptic bronchoscope was first used in diagnosing tuberculosis in 1975, to establish the diagnosis of tuberculosis in patients presenting with clinical and radiological manifestations suggestive of pulmonary tuberculosis, but having negative sputum for AFB by direct microscopic sputum examination. (6)