Tuberculosis may be underestimated in Rwandan women

The majority of adult tuberculosis (TB) cases reported to the surveillance system in Rwanda are male. If this results from detection mechanisms that are less sensitive to TB in women, notified cases should be more severe in women than in men.

We analysed the 2006 series of TB cases among persons aged ≥ 15 years in Huye District and Kigali. Severe TB was defined as disease leading to death, or extra-pulmonary or disseminated TB.

Of 1673 cases identified, 40% involved women, who were younger than men (65% vs. 54% aged <35 years). Overall severity was similar in both sexes. Considering age <35 years, women were at higher risk of severe TB than men, although the difference was not statistically significant. Smear-negative pulmonary TB (SNPTB), and human immunodeficiency virus (HIV) infection were more frequent in women than in men (59% vs. 42%, P < 0.001). For women with smear-positive pulmonary TB (SPPTB), the risk of death was twice that among men (adjusted hazard ratio 1.8; 95%CI 1.0-3.2).

Among female TB patients, the higher risk of death with SPPTB, the higher frequency of SNPTB and the higher prevalence of HIV infection suggest that the passive system of case detection may underestimate the burden of TB in Rwandan women.