IDENTIFICATION OF A KLEBSIELLA-PNEUMONIAE STRAIN ASSOCIATED WITH NOSOCOMIAL URINARY-TRACT INFECTION

To differentiate between relapse of infection and reinfection of the u rinary tract due to Klebsiella pneumoniae, 33 K. pneumoniae isolates c ollected from 20 patients with spinal cord injury (SCI) over 2 years w ere typed ibg genomic fingerprinting by repetitive-element PCR. Clinic al isolates obtained from tile same patients with recurrent episodes o f urinary tract infection (UTI) revealed identical genomic fingerprint s indicating relapse of UTI due to K. pneumoniae, despite appropriate antibiotic therapy, Seventeen isolates obtained from 8 of the 20 SCI p atients shared a common genotype, termed RD6. Among non-SCI patients r esiding in other nursing units, the RDC genotype was found in 5 of 10 patients with K. pneumoniae UTI but in only 1 of 20 patients with K. p neumoniae infection that did not involve the urinary tract, suggesting a strong association of this genotype with UTI, All RD6 isolates exhi bited strong adherence (greater than or equal to 50 adherent bacteria per cell) to HEp-2 cells, whereas other K. pneumoniae isolates general ly did not adhere to or adhered very weakly to HEp-2 cells (less than or equal to 5 adherent bacteria per cell), Adherence was inhibited eit her by 4% D-mannose or by anti-type 1 fimbrial rabbit serum, These res ults suggest that the capacity of K. pneumoniae RD6 isolates to cause UTI may be mediated by its striking adherence to mammalian cells.