title: Comparative in vitro activity of carbapenems against major Gram-negative pathogens: results of Asia-Pacific surveillance from the COMPACT II study.
abstract: Resistance rates amongst Gram-negative pathogens are increasing in the Asia-Pacific region. The Comparative Activity of Carbapenem Testing (COMPACT) II study surveyed the carbapenem susceptibility and minimum inhibitory concentrations (MICs) of doripenem, imipenem and meropenem against 1260 major Gram-negative pathogens isolated from hospitalised patients at 20 centres in five Asia-Pacific countries (New Zealand, the Philippines, Singapore, Thailand and Vietnam) during 2010. Pseudomonas aeruginosa (n=625), Enterobacteriaceae (n=500), and other Gram-negative pathogens including Acinetobacter baumannii (n=135) were collected from patients with bloodstream infection (32.2%), nosocomial pneumonia including ventilator-associated pneumonia (58.1%), and complicated intra-abdominal infection (9.7%), with 36.7% being isolated from patients in an Intensive Care Unit. As high as 29.8% of P. aeruginosa and 73.0% of A. baumannii isolates were not susceptible to at least a carbapenem, whereas the majority of Enterobacteriaceae (97.2%) were susceptible to all carbapenems. Respective MIC(50)/MIC(90) values (MICs for 50% and 90% of the organisms, respectively) of doripenem, imipenem and meropenem were: 0.38/8, 1.5/32 and 0.38/16 mg/L for P. aeruginosa; 0.023/0.094, 0.25/0.5 and 0.032/0.094 mg/L for Enterobacteriaceae; and 32/64, 32/128 and 32/64 mg/L for A. baumannii. Doripenem and meropenem had comparable activity against P. aeruginosa, both being more active than imipenem. All carbapenems were highly potent against Enterobacteriaceae, although imipenem demonstrated higher MIC values than doripenem and meropenem. The three carbapenems showed less activity against A. baumannii. The high prevalence of carbapenem resistance amongst important nosocomial pathogens (P. aeruginosa and A. baumannii) warrants rigorous infection control measures and appropriate antimicrobial use in the Asia-Pacific region.
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok-Noi, Bangkok 10700, Thailand. sipkr@mahidol.ac.th
authors.forename: Pattarachai
authors.initials: P
authors.lastname: Kiratisin
authors.forename: Anan
authors.initials: A
authors.lastname: Chongthaleong
authors.forename: Thean Yen
authors.initials: TY
authors.lastname: Tan
authors.forename: Evelina
authors.initials: E
authors.lastname: Lagamayo
authors.forename: Sally
authors.initials: S
authors.lastname: Roberts
authors.forename: Jemelyn
authors.initials: J
authors.lastname: Garcia
authors.forename: Todd
authors.initials: T
authors.lastname: Davies
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001208:Asia / Q000453:epidemiology; D015780:Carbapenems / Q000494:pharmacology*; D003428:Cross Infection / Q000097:blood / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D005843:Geography; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification / Q000472:pathogenicity; D016905:Gram-Negative Bacterial Infections / Q000097:blood / Q000382:microbiology; D006801:Humans; D020128:Inhibitory Concentration 50; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D010139:Pacific Islands / Q000453:epidemiology; D011159:Population Surveillance / Q000379:methods; D015995:Prevalence; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D001618:beta-Lactamases