In vitro susceptibilities of aerobic and facultative anaerobic Gram-negative bacilli isolated from patients with intra-abdominal infections at a medical center in Taiwan: results of the Study for Monitoring Antimicrobial Resistance Trends (SMART) 2002-2006.
OBJECTIVE
The Study for Monitoring Antimicrobial Resistance Trends (SMART) was initiated to monitor the in vitro antimicrobial susceptibility of aerobic and facultative anaerobic Gram-negative bacilli (GNB) isolated from patients with intra-abdominal infections (IAI). This report summarizes the SMART data from 1 of the study centers from 2002 to 2006.


METHODS
492 Gram-negative isolates were collected from 482 patients with IAI. Susceptibilities of these isolates to 12 antimicrobial agents were determined using the broth microdilution method.


RESULTS
Enterobacteriaceae comprised 68.3% of the isolates (n = 336). The 4 main species were Klebsiella spp. (n = 129; 26.2%), Escherichia coli (n = 122; 24.8%), Enterobacter spp. (n = 36; 7.3%), and Aeromonas hydrophila (n = 35; 7.1%). The commonest glucose non-fermentative GNB were Acinetobacter baumannii (n = 46; 9.3%) and Pseudomonas aeruginosa (n = 35; 7.1%). Extended-spectrum beta-lactamase (ESBL) production was detected in 70 Enterobacteriaceae isolates (70/336; 21%). The ESBL phenotype was exhibited by 23% of Klebsiella pneumoniae, 26% of E. coli, and 19% of Enterobacter spp. The highest rate of ESBL production was found in 2005 for E. coli (38%) and in 2003 for Klebsiella spp. (38%) and Enterobacter spp. (40%). The incidence of ESBL-producing isolates declined in 2005 and 2006. Low susceptibility rates of E. coli isolates to ciprofloxacin (58%) and levofloxacin (64%) were noted. Ertapenem (99%), imipenem (99%), and amikacin (94%) were the most potent agents against Enterobacteriaceae spp.


CONCLUSIONS
Continuous surveillance is crucial to monitor the trend of antimicrobial resistance patterns among GNB isolated from IAI.
Chen
Wei Yu
WY
Division of Infectious Diseases, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
Jang
Tsrang Neng
TN
Huang
Chien Hsien
CH
Hsueh
Po Ren
PR
D034841:Abdominal Cavity / Q000382:microbiology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000453:epidemiology / Q000382:microbiology; D006088:Gram-Negative Aerobic Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology; D006092:Gram-Negative Facultatively Anaerobic Rods / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D015994:Incidence; D008826:Microbial Sensitivity Tests; D011159:Population Surveillance / Q000379:methods; D013624:Taiwan / Q000453:epidemiology
D000900:Anti-Bacterial Agents