Different trends in antibiotic resistance rates at a university teaching hospital.
OBJECTIVE
To investigate long-term trends in antibiotic resistance of common bacterial species isolated at a university hospital and in its intensive care units (ICUs).


METHODS
Levels of antibiotic resistance of common bacterial pathogens were investigated at the Karolinska Hospital during the 12-year period 1988-99. Resistance rates were analyzed for the entire hospital, as well as for ICUs combined.


RESULTS
At the Karolinska Hospital, we found increased ciprofloxacin resistance among Escherichia coli isolates, from 0% in 1991 to 11% in 1999. In the ICUs, the corresponding increase was from 0% to 4.8% during the same period. Co-trimoxazole resistance levels increased from 7.5% to 14%, with lower levels for the ICUs. For ampicillin, cefuroxime, and gentamicin, the levels of resistance were similar in the whole hospital and in the ICUs. Among Pseudomonas aeruginosa isolates, imipenem resistance was higher in the ICUs. For ciprofloxacin, resistance increased from 2.5% in 1991 to 13% in 1999 in the whole hospital, with similar figures for the ICUs.


CONCLUSIONS
The resistance rates at the Karolinska Hospital were still generally low, but were increasing for some antibiotic-microbe combinations. The results emphasize the importance of including all sectors of a hospital in resistance surveillance studies, and also the value of long surveillance periods.
Sörberg
M
M
Department of Medicine, Karolinska Institute, Karolinska Hospital, Stockholm, Sweden. mikael.sorberg@ks.se
Farra
A
A
Ransjö
U
U
Gårdlund
B
B
Rylander
M
M
Settergren
B
B
Kalin
M
M
Kronvall
G
G
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000175:diagnosis; D006785:Hospitals, University; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D011552:Pseudomonas Infections / Q000175:diagnosis; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000302:isolation & purification
D000900:Anti-Bacterial Agents