Comparison of antimicrobial resistance of Acinetobacter baumannii clinical isolates from Shanghai and Hong Kong.
OBJECTIVE
To compare the antimicrobial resistance patterns of Acinetobacter baumannii isolates from Shanghai and Hong Kong.


METHODS
A total of 212 A. baumannii strains of one isolate per patient were collected from Shanghai and Hong Kong from August 2002 to August 2003 that were tested against 15 commonly used antimicrobial agents by the agar dilution method according to the NCCLS guidelines.


RESULTS
Most beta-lactams showed no significant increase in activity after adding beta-lactamase inhibitors. The resistance rates of the isolates against ticarcillin-clavulanate, piperacillin-tazobactam and ampicillin-sulbactam were for Shanghai 74.9, 70.9, 69.1% and Hong Kong 24.3, 18.9, 13.5%, respectively. Only cefoperazone-sulbactam showed a significant increase in activity against both Shanghai and Hong Kong strains, as the resistance rates dropped from 93.7 to 8.6% and 83.8 to 5.4%, respectively. The resistance rates of ceftazidime, cefepime, and gentamicin against Shanghai strains were 69.7, 72.0, 73.7% and Hong Kong strains 69.7, 29.7, 18.9%, respectively. About 65% of Shanghai strains were found to be amikacin-resistant, however, all Hong Kong strains were sensitive. Fluoroquinolones including ciprofloxacin and levofloxacin had resistance rates over 60% against Shanghai strains, but only 13.5% against Hong Kong strains. Shanghai strains had imipenem and meropenem resistance rate of 6.3%. Though 10.8% Hong Kong strains were resistant to meropenem, only 2.7% of them were resistant to imipenem.


CONCLUSIONS
A. baumannii isolated from Shanghai were more resistant to all drugs except meropenem than Hong Kong isolates. The results indicate a need for measures to control the abuse of antibiotic usage in order to prevent the emergence of more multidrug-resistant isolates in both cities.
Ling
Thomas K W
TK
Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, SAR, China. lingt@cuhk.edu.hk
Ying
Chun Mei
CM
Lee
Ching Ching
CC
Liu
Zhi Kai
ZK
D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D000583:Amikacin / Q000494:pharmacology; D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002681:China; D019818:Clavulanic Acid / Q000494:pharmacology; D003428:Cross Infection / Q000188:drug therapy / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial; D004791:Enzyme Inhibitors / Q000494:pharmacology; D024841:Fluoroquinolones / Q000494:pharmacology; D006723:Hong Kong; D006801:Humans; D015378:Imipenem / Q000494:pharmacology; D000077731:Meropenem; D008826:Microbial Sensitivity Tests; D010397:Penicillanic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D010878:Piperacillin / Q000494:pharmacology; D013407:Sulbactam / Q000494:pharmacology; D000078142:Tazobactam; D013845:Thienamycins / Q000494:pharmacology; D013982:Ticarcillin / Q000494:pharmacology; D018440:beta-Lactam Resistance; D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D024841:Fluoroquinolones; D013845:Thienamycins; D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams; D019818:Clavulanic Acid; D015378:Imipenem; D000667:Ampicillin; D000583:Amikacin; D010397:Penicillanic Acid; D013982:Ticarcillin; D000077731:Meropenem; D013407:Sulbactam; D000078142:Tazobactam; D010878:Piperacillin