Ralstonia spp.: emerging global opportunistic pathogens.

The bacterial genus Ralstonia (Gram-negative non-fermenters) is becoming more prevalent in cases of infection with three bacterial species, Ralstonia pickettii, Ralstonia insidiosa and Ralstonia mannitolilytica, making up all cases reported (in the literature) to date. These organisms are prevalent in many different types of water supplies (including hospital water supplies), being well adapted to survive in low-nutrient conditions. They have been shown to cause infections, sometimes serious, such as osteomyelitis and meningitis, in hospital settings. Seventy cases of R. pickettii, 13 cases of R. mannitolilytica and three cases of R. insidiosa infection have been identified from the literature. Insight is given into the types of infections that are caused by these bacteria, the underlying conditions that are associated with these infections and potential treatments.