EPIDEMIOLOGIC INVESTIGATION OF INFECTIONS DUE TO ALCALIGENES SPECIES IN CHILDREN AND PATIENTS WITH CYSTIC-FIBROSIS - USE OF REPETITIVE-ELEMENT-SEQUENCE POLYMERASE CHAIN-REACTION

Twenty-one isolates of Alcaligenes species were recovered from the res piratory tract of 16 patients at Texas Children's Hospital over a 1-ye ar period. All but one were identified as Alcaligenes xylosoxidans; th e remaining isolate was identified as Alcaligenes faecalis (formerly A lcaligenes odorans). Thirteen of 21 isolates were from the sputum of e ight patients with cystic fibrosis (CF), two of whom were persistently colonized. The remaining isolates were recovered from intubated child ren. Patterns produced by repetitive-element-sequence polymerase chain reaction (rep-PCR), with use of either repetitive extragenic palindro mic (REP) or enterobacterial repetitive intergenic consensus (ERIC) pr imers, showed that strains from different patients were distinct. This observation ruled out a common-source outbreak. Strains repeatedly cu ltured from the two persistently colonized patients over several month s had identical rep-PCR patterns. We conclude that, similar to Pseudom onas aeruginosa, Alcaligenes species (most often A. xylosoxidans) colo nize the respiratory tract of intubated children and of patients with CF. Colonization of patients with CF was associated with an exacerbati on of pulmonary symptoms.