The laboratory diagnosis of melioidosis.

The recognition of unusual, but important, pathogens such as Burkholderia pseudomallei is essential for the rapid implementation of appropriate antimicrobial therapy--delays can be fatal. Melioidosis should be considered as a potential diagnosis for any patient with exposure to areas of endemicity, and thus laboratories should be aware of the differential features of the disease and the causative organism. Isolation of B. pseudomallei is readily achieved using standard culture media such as blood, MacConkey or cystine-lactose-electrolyte-deficient (CLED) agars, and routine blood culture broths. Selective media, Ashdown's agar and selective broth, are required for respiratory tract specimens to ensure reliable isolation from amongst the normal or contaminating flora. These media are easily prepared from common media constituents. Colonial morphology and simple biochemical tests will suggest the identity of the organism, which can then be confirmed by additional tests for 'non-fermenters', such as the API 20NE.