Antibiotic susceptibility patterns of respiratory isolates of Klebsiella pneumoniae in Europe and the USA in 1992 and 1993

The overall antibiotic susceptibility of Klebsiella pneumoniae isolates collected in 1992 (n = 35) and 1993 (n = 85) was highly variable ranging from 0.8% for amoxycillin to 95.8% for ceftriaxone. On a weight for weight basis, the activity of the compounds decreased in the following sequence : ceftriaxone, cefixime, co-trimoxazole, ciprofloxacin, ofloxacin, cefaclor, amoxycillin/clavulanate, doxycycline, cefuroxime, chloramphenicol, amoxycillin. A small percentage of resistant strains was found for each of the compounds (between 0.8% for ceftriaxone and 12.5% for chloramphenicol) with the exception of amoxycillin which was almost uniformly resistant. There was a trend for the percentage of resistant strains to increase between the two study years for all compounds except for chloramphenicol. Resistance to β-lactams in France and the USA is likely to have been due to strains producing extended spectrum β-lactamases.