title: Antimicrobial susceptibility and extended-spectrum beta-lactamase rates in aerobic gram-negative bacteria causing intra-abdominal infections in Vietnam: report from the Study for Monitoring Antimicrobial Resistance Trends (SMART 2009-2011).
abstract: Treatment options for multidrug-resistant pathogens remain problematic in many regions and individual countries, warranting ongoing surveillance and analysis. Limited antimicrobial susceptibility information is available for pathogens from Vietnam. This study determined the bacterial susceptibility of aerobic gram-negative pathogens of intra-abdominal infections among patients in Vietnam during 2009-2011. A total of 905 isolates were collected from 4 medical centers in this investigation as part of the Study for Monitoring Antimicrobial Resistance Trends. Antimicrobial susceptibility and extended-spectrum beta-lactamase (ESBL) rates among the appropriate species were determined by a central laboratory using Clinical and Laboratory Standards Institute methods. Among the species collected, Escherichia coli (48.1% ESBL-positive) and Klebsiella pneumoniae (39.5% ESBL-positive) represented the majority (46.4%) of the isolates submitted for this study. Ertapenem MIC90 values were lowest for these 2 species at 0.12 and 0.25μg/mL and remained unchanged for ESBL-positive isolates. Imipenem MIC90 values were also the same for all isolates and ESBL-positive strains at 0.25 and 0.5μg/mL, respectively. Ertapenem MIC90 values for additional species with sufficient numbers for analysis, including Enterobacter cloacae, Proteus mirabilis, Acinetobacter baumannii, and Pseudomonas aeruginosa, were 1, 0.06, >4, and >4μg/mL, respectively. Analysis of beta-lactamases in a subset of 132 phenotypically ESBL-positive Enterobacteriaceae demonstrated that CTX-M variants, particularly CTX-M-27 and CTX-M-15, were the predominant enzymes. High resistance rates in Vietnam hospitals dictate continuous monitoring as antimicrobial inactivating enzymes continue to spread throughout Asia and globally.
authors.affiliation: International Health Management Associates, Inc., Schaumburg, IL, USA. Electronic address: dbiedenbach@ihmainc.com.
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Biedenbach
authors.affiliation: International Health Management Associates, Inc., Schaumburg, IL, USA.
authors.forename: Samuel K
authors.initials: SK
authors.lastname: Bouchillon
authors.affiliation: International Health Management Associates, Inc., Schaumburg, IL, USA.
authors.forename: Daryl J
authors.initials: DJ
authors.lastname: Hoban
authors.affiliation: International Health Management Associates, Inc., Schaumburg, IL, USA.
authors.forename: Meredith
authors.initials: M
authors.lastname: Hackel
authors.affiliation: Bach Mai Hospital, Hanoi, Vietnam.
authors.forename: Doan Mai
authors.initials: DM
authors.lastname: Phuong
authors.affiliation: Cho Ray Hospital, Ho Chi Minh City, Vietnam.
authors.forename: Tran Thi Thanh
authors.initials: TT
authors.lastname: Nga
authors.affiliation: Binh Dan Hospital, Ho Chi Minh City, Vietnam.
authors.forename: Nguyen Tran My
authors.initials: NT
authors.lastname: Phuong
authors.affiliation: Viet Duc Hospital, Hanoi, Vietnam.
authors.forename: Tran Thi Lan
authors.initials: TT
authors.lastname: Phuong
authors.affiliation: International Health Management Associates, Inc., Schaumburg, IL, USA.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Badal
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015780:Carbapenems / Q000494:pharmacology; D003428:Cross Infection; D024881:Drug Resistance, Bacterial; D000077727:Ertapenem; D006090:Gram-Negative Bacteria / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology*; D006801:Humans; D059413:Intraabdominal Infections / Q000453:epidemiology* / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D014744:Vietnam / Q000453:epidemiology; D001618:beta-Lactamases / Q000235:genetics*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D047090:beta-Lactams; D001618:beta-Lactamases; D000077727:Ertapenem
keywords: ESBL; Resistance; SMART study; Vietnam