Clinical risk factors for melioidosis

Although melioidosis can affect previously healthy patients, several comorbidities appear tobe strongly associated with disease. Case control and population-based studies have defined an increased risk of melioidosis in patients with diabetes, hazardous alcohol intake, renal disease, immunosuppression and thalassaemia. These specific comorbidities provide clues to pathogenesis of melioidosis, suggesting that immune dysfunction specifically affecting innate immunity, such as neutrophil function, is an important mechanism rather than conditions affecting adaptive immune function, such as infection with human immunodeficiency virus (HIV). Despite the demonstration of a cell-mediated response to Burkholderia pseudomallei, HIV infection does not appear to be a significant risk factor for disease, further supporting that adaptive immunity may have a limited role in protecting against infection. Exposure to mud and pooled surface water in endemic areas is an important and potentially preventable risk in susceptible patients.