Hypersensitivity reactions to dapsone: a systematic review.

Dapsone is widely used in the treatment of leprosy and several chronic inflammatory dermatological conditions. Hypersensitivity reactions to dapsone are potentially fatal adverse drug reactions with unknown prevalence and risk factors. We performed a systematic review covering all reported cases of hypersensitivity reactions, in order to systematically summarize the published evidence on prevalence, clinical course and fatality rate. Articles were identified through standardized search strategies. Included studies were reviewed for hypersensitivity characteristics and odds ratios were calculated in univariate and multivariate regression models to assess the risk factors for fatal outcome. A total of 114 articles (17 epidemiological studies, 97 case reports) totalling 336 patients with hypersensitivity reactions were included for analysis. From the epidemiological studies a total hypersensitivity reaction prevalence rate of 1.4% (95% confidence interval 1.2–1.7%) was determined. Mucosal involvement, hepatitis, higher age and disease occurrence in non-affluent countries were associated with higher risk of fatal outcome. Overall, the fatality rate was 9.9%.