Pulmonary tuberculosis in the border region of Chiapas, Mexico.

To estimate the prevalence of pulmonary tuberculosis (PTB) in chronic cough patients seeking care at a second level hospital for any complaint, and to identify groups more likely to test TB smear-positive, within the Border Region of Chiapas, Mexico.Active case finding of patients with chronic cough (cough of 15 days or more) was carried out among all patients aged over 14 years seeking care for whatever reason in the only hospital in the region for patients not covered by insurance. The coughers identified (n=221) were interviewed and three sputum samples requested for acid-fast smears. In order to identify groups at greater risk a logistic regression model was constructed.A rate of 21 positive PTB smears per hundred patients was found (95% Confidence Interval [CI]=15.5-26.6). The main factors associated with positive PTB were age, occupation and weight loss. The subgroup of chronic cough patients of those aged 35-44 years, agricultural workers and those who had lost weight, had the greatest likelihood of positive PTB smears (68.7%).In hospitals that treat rural patients, special efforts should be made to make health personnel more aware of the need to investigate respiratory symptoms in all of their patients, particularly in the subgroups identified with the greatest likelihood of being positive for TB.