Identification and distribution of Achromobacter species in cystic fibrosis

BackgroundWe recently described a multilocus sequence typing scheme for Achromobacter that identified several novel species in this genus.MethodsWe assessed the ability of nrdA sequence analysis to differentiate Achromobacter species, including the seven previously named species and 14 recently described genogroups. Confirmation of distinctness between groups was confirmed using the k parameter. Using this single locus sequence to differentiate species, we analyzed Achromobacter isolates obtained from 341 CF patients in the U.S.ResultsWe found that Achromobacter xylosoxidans accounts for 42% of Achromobacter infections, while Achromobacter ruhlandii accounted for 23.5% of infections. Isolates from 17% of patients were members of the novel genogroup 14. The remaining 17.5% of strains belonged to 11 other species/genogroups.ConclusionThe use of nrdA sequence analysis allows differentiation of the several Achromobacter species that can infect persons with CF. Achromobacter species other than A. xylosoxidans account for the majority of Achromobacter infection in CF patients in the U.S.