Approach to melioidosis

Burkholderia pseudomallei, the causative agent of melioidosis, is endemic in tropical and subtropical regions where it is a cause of community-acquired sepsis. Much of the global burden is in the Asia-Pacific region, however melioidosis remains under-reported and the known area of endemicity has expanded to include countries in Africa and the Americas, including the Southern USA. Infection is via environmental exposure to soil and water, and may occur via (sometimes minor) skin trauma, inhalation during severe weather, or ingestion of untreated water. Those with diabetes, hazardous alcohol consumption, chronic kidney disease, and other immune suppression are most at risk. The clinical manifestations are protean, and include pneumonia, abscesses of internal organs, non-healing ulcers, bone and joint infection, and encephalomyelitis. Diagnosis is made when B. pseudomallei is isolated from clinical specimens. Over half of patients have positive blood cultures. To prevent relapse, prolonged therapy is needed; this includes at least 10-14 days of intravenous ceftazidime, meropenem, or imipenem, and at least 3 months of oral trimethoprim-sulfamethoxazole. There is no licensed vaccine available, however phase 1 clinical trials of vaccine candidates will soon commence.