Identification of respiratory isolates of Stenotrophomonas maltophilia by commercial biochemical systems and species-specific PCR

One hundred strains of Stenotrophomonas maltophilia isolates from respiratory specimens were biochemically identified using the API 20NE strip and the VITEK®2 ID-GNB card. The identification was confirmed by a species-specific PCR using two primers specific for the 23S rRNA gene.The API 20NE showed only 1 strain with “low discrimination” whereas the VITEK®2 gave 12. In any case, the two biochemical systems showed good reliability compared to SS-PCR.