Leptospirosis: a worldwide resurgent zoonosis and important cause of acute renal failure and death in developing nations.

Leptospirosis, a spirochetal zoonosis, is a globally re-emerging infectious disease that has disseminated from its habitual rural base to become the cause of urban epidemics in poor communities of industrialized and developing nations. This review addresses the issues in the epidemiology, clinical features, and management of the disease, as well as progress made toward understanding the pathogenesis of leptospiral nephropathy. In developing nations, leptospirosis plays an important role as a potentially preventable cause of acute renal failure. The data indicate that in certain developing regions, such as the city of Salvador, Brazil, leptospirosis is misdiagnosed with other infectious disease such as dengue and the overall disease burden is likely underestimated partly because of the protean and nonspecific presentation. Severe forms of the disease are associated with high case-fatality rate. In urban Brazil, outbreaks of leptospirosis can be predicted by heavy rain and flooding and this may serve to indicate which resources should be allocated to prevent the disease. Advancements in the basic research and epidemiology of leptospirosis should contribute to the development of more accurate diagnostic tests and of an effective vaccine. Policy makers should be urged to address the underlying conditions of poverty as well as environmental issues, which have led to the emergence of leptospirosis.