In vitro susceptibilities of aerobic and facultatively anaerobic gram-negative bacilli isolated from patients with intra-abdominal infections worldwide: 2005 results from Study for Monitoring Antimicrobial Resistance Trends (SMART).
BACKGROUND
The Study for Monitoring Antimicrobial Resistance Trends (SMART) is examining aerobic and facultatively anaerobic gram-negative bacilli (GNB) isolated from intra-abdominal infections. This report summarizes the 2005 annual data.


METHODS
During 2005, 76 medical centers in 31 countries in five regions collected intra-abdominal GNB for antimicrobial susceptibility testing using broth microdilution according to the Clinical and Laboratory Standards Institute guidelines.


RESULTS
A total of 5,476 unique aerobic and facultatively anaerobic GNB were isolated. Enterobacteriaceae accounted for 86% (4,711) of the total isolates. Among the 12 antimicrobial agents tested, the carbapenems and amikacin were the most reliably active against the Enterobacteriaceae, whereas ampicillin/sulbactam most often was the least active. Escherichia coli was the species most commonly isolated, at 48% (2,654). Extended-spectrum beta-lactamases (ESBLs) were detected phenotypically in 12% (325/2,329) of E. coli and 18% (151/856) of Klebsiella spp. In general, ESBL producers demonstrated lower susceptibility to the majority of the antibiotics than the non-producers; however, ESBL producers usually were susceptible to the carbapenems tested.


CONCLUSIONS
In 2005, antibiotic resistance continued to be a problem among GNB isolated from intra-abdominal infections, with the highest resistance rates observed in the Asia/Pacific region. Imipenem-cilastatin, ertapenem, and amikacin were the agents most consistently active in vitro against the Enterobacteriaceae isolated.
Baquero
Fernando
F
Hospital Ramon y Cajal, Madrid, Spain.
Hsueh
Po-Ren
PR
Paterson
David L
DL
Rossi
Flávia
F
Bochicchio
Grant V
GV
Gallagher
Gale
G
Lantz
Keith
K
Villasenor
Javier Baez
JB
McCarroll
Kathleen
K
Abramson
Murray A
MA
Chow
Joseph W
JW
D034841:Abdominal Cavity / Q000382:microbiology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects; D014943:Global Health; D006088:Gram-Negative Aerobic Bacteria / Q000187:drug effects*; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D006092:Gram-Negative Facultatively Anaerobic Rods / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests; D011159:Population Surveillance; D018440:beta-Lactam Resistance
D000900:Anti-Bacterial Agents