Yield of gastric lavage and bronchial wash in pulmonary tuberculosis

OBJECTIVE: TO determine the yield of acid-fast bacilli (AFB) in gastric lav age and bronchial washing in adult patients clinically and radiologically s uspected of pulmonary tuberculosis but who cannot produce sputum. METHODS: Selected adult patients were admitted to the ward; gastric lavage was done for 3 consecutive days after an overnight fast followed by bronchi al wash. Specimens were immediately sent to laboratory for AFB direct smear and culture. RESULTS: The yield of AFB in gastric lavage on direct smear was 16/20 (80%) and 12/20 (60%) in the first and second samples, respectively. When combin ed, 18/20 (90%) were direct smear positive, while the third sample did not increase the yield. The yield of AFB culture in gastric lavage was 6/20 (30 %) in both the first and second samples, while the combined results of the first and second samples were 8/20 (40%). The third sample did not increase the yield. In bronchial wash, AFB direct smear was positive in 18/20 (30%) , while culture was positive in 14/20 (70%). CONCLUSION: Gastric lavage and bronchial washing are useful methods for the diagnosis of pulmonary tuberculosis in patients who cannot produce sputum. Two gastric lavage specimens are adequate. On comparison, bronchial wash i s superior to gastric lavage in culture, but their yield on direct smear is equal.