Clinico-pathological profile and treatment outcome in smear negative pulmonary tuberculosis patients at a teaching hospital

Tuberculosis remains the single highest contributor to the world's morbidity and mortality. Early diagnosis and prompt treatment is essential to prevent its transmission. To see the treatment response of anti tuberculosis drugs in smear negative patients and study the predictors of culture positive among smear negative tuberculosis patients. Ninety four sputum smear negative patients clinically and radiologically suggestive of tuberculosis were selected. These patients were put on anti tuberculosis drugs without waiting for their culture results. They were then followed for 8 months to see their treatment outcome. A total of 94 smear negative patients were selected and given anti tuberculosis treatment. Of these 37(39%) were culture positive and 57(61%) were culture negative. Of the 37 culture positive patients 36(97%) showed clinical or radiological improvement as compared to 46(81%) out of 57 in culture negative cases. Symptoms of cough with sputum production was significantly associated with culture positivity. On x-ray chest moderate lesion with diffuse infiltration was more common finding in 64% while extensive and cavitatory lesion was seen in 24% of all cases. Association of extensive and cavitatory lesion were seen in culture positive group. Response to anti tuberculosis drugs in sputum smear negative tubercolosis suspects was found to be effective in majority of the patients. Cough, sputum and extensive cavitatory lung lesion were the predictors of culture positive cases. There is need to train physicians on the use of anti tuberculosis therapy in smear negative suspected pulmonary tuberculosis cases, especially if they have productive cough and cavitatory lung lesions. (author)