Molecular epidemiology of Burkholderia cepacia, Stenotrophomonas maltophilia, and Alcaligenes xylosoxidans in a cystic fibrosis center.

Burkholderia cepacia, Stenotrophomonas maltophilia, and Alcaligenes xylosoxidans have been isolated with increasing frequency from the sputum of patients with cystic fibrosis in a pediatric hospital. In 1994-95, 27 of 120 patients were persistently colonized, 17 with Burkholderia cepacia, eight with Alcaligenes xylosoxidans, and five with Stenotrophomonas maltophilia. Genotyping of 220 clinical isolates revealed that most of the Burkholderia cepacia strains were clonally related, suggesting either cross-infection or a common source of exposure. In contrast, neither cross-infection nor a common source of exposure appear to have occurred in the cases of Alcaligenes xylosoxidans or Stenotrophomonas maltophilia.