TABLE 3.

Clinical and bacteriological features of the K. pneumoniae isolates

GroupStrainClinical features Virulence test Resistance to antimicrobial agentsd
β-Lactams Non-β-lactams
InfectionaOrigin of infectionbDate of isolation (mo/yr)MortalityDose (CFU/mouse)cSurvival (days)First-generation cephalosporinsSecond-generation cephalosporinsThird-generation cephalosporinsCephamycinChloramphenicolGentamicinQuinolonesTetracyclineTMP/SMX
1NK11, 3C5/1993Y20,0007
NK92C11/1996Y503
NK2522C10/2002Y5005
NK61, 3C10/1995Y2,0002
NK72C11/1993Y5004
2NK21, 5H5/1993NNA>7RRRR
NK2453H1/2002NNA>7RRRRRRR
NK254H1/1999NNA>7RRRRR
NK293H2/1999NNA>7RRRRR
NK276H2/1999NNA>7RRRRR
NK31, 4C7/1993NNA>7
NK41H8/1993NNA>7
3NK82C9/1996NNA>7RRR
NK102C12/1996NNA>7
NK51C3/1994Y503
  • a 1, bacteremia; 2, liver abscess; 3, urinary tract infection; 4, pneumonia; 5, aspiration pneumonia; 6, surgical wound infection.

  • b C, community acquired; H, hospital acquired.

  • c NA, not available.

  • d R, resistant. The first-generation cephalosporins were cephalothin and cefazolin; the second-generation cephalosporin was cefuroxime; the third-generation cephalosporins were ceftriaxone and either cefotaxime or ceftazidime; and the quinolones were nalidixic acid and the fluoroquinolones ciprofloxacin and levofloxacin. TMP/SMX, trimethoprim-sulfamethoxazole. The three isolates resistant to cephamycin (cefoxitin) in group 2 are also resistant to amoxicillin-clavulanic acid and/or ticarcillin-clavulanic acid. All isolates were resistant to ampicillin, and all isolates were susceptible to amikacin, cefepime, and imipenem.