Smear positive pulmonary tuberculosis patients were diagnosed using the following criteria as per the RNTCP guidelines: (i) Two or three smears positive for AFB and (ii) One sputum smear positive for AFB with radiographic abnormalities consistent with active pulmonary tuberculosis. Smear negative pulmonary tuberculosis was diagnosed if three sputum smears were negative for AFB but evidence of radiographic abnormalities of active tuberculosis was present after two weeks of antibiotic treatment for routine bacterial infections of the respiratory tract19. Detection of HIV infection: All patients were given pre-test counselling and tested for anti-HIV antibodies by enzyme-linked immunosorbent assay (ELISA) (Detect HIVMC, Biochem.
