Smear-negative, culture-positive pulmonary tuberculosis among patients with chronic cough in Cotonou, Benin.

Setting: The main tuberculosis (TB) centre in Benin, West Africa, where only 2% of adult pulmonary TB cases are sputum smear-negative, all other pulmonary cases being smear-positive.

Objectives: To assess the burden of smear-negative, culture-positive pulmonary TB among TB suspects in Cotonou, and to estimate the total number of non-smear-positive TB cases at country level.

Design: For 1 year, one morning sputum culture was performed for every TB suspect (cough lasting >3 weeks, as defined in Benin's national guidelines) with three negative sputum smears (fluorescence technique).