Source of Support: None, Conflict of Interest: None
Bacteriological assessment of 60 pulmonary tuberculosis patients on short course chemotherapy and 66 patients on retreatment was made at the time of their retrieval after various periods of treatment default. Persistence and reappearance of tubercle bacilli were more frequently observed 1) In the defaulters who stayed away during the early phase of treatment, 2) In those who had longer duration of default and 3) In patients with moderately advanced and far advanced pulmonary tuberculosis. All the post-default culture growths of M. tuberculosis were found to be sensitive to all the anti tuberculosis drugs administered during pre-default period. Therefore, the same drug regimens could be reinstituted or continued without any alteration after the treatment default.