Back

ICU antimicrobial susceptibility rates among Gram-negative bacilli isolated from infections in the USA: results from ICU surveillance study 2005

Abstract number: 1733_159

Gallagher G., Wilson H., Abramson M.

Background: ISS (ICU Surveillance Study) is an ongoing US antimicrobial surveillance programme that has focused on infections from Intensive Care Units (ICU). The objective of this analysis was to assess antimicrobial susceptibility patterns among aerobic & facultative Gram-negative bacilli recovered at participating sites in the USA during 2005.

 Pseudomonas aeruginosaEscherichia coliKlebsiella pneumoniaeEnterobacter cloacaeAcinetobacter baumanniiSerratia marcescens
ErtapenemN/A988998N/A96
Imipenem769993997897
Cefepime629173703391
Cefotaxime89578622278
CefoxitinN/A90767N/A29
Ceftazidime718971543883
Ceftriaxone188971542986
Amp/Sulbactam2526016504
Pip/Tazobactam819478753883
Amikacin849883967396
Gentamicin578881863990
Tobramycin738774856385
Ciprofloxacin607676863789
Lexofloxacin607779903895
Aztreonam598971571287

Methods: 39 centres in the USA each tested the in vitro activity of 15 antimicrobial agents. Consecutive unique Gram-negative bacilli from all body sites were tested using microdilution techniques according to CLSI guidelines and breakpoints. Production of extended-spectrum b-lactamases (ESBL) was confirmed in isolates with a MIC of ceftriaxone, ceftazidime, or cefepime ≥2 mg/mL by comparing ceftazidime, cefotaxime, and cefepime MICs with and without clavulanate.

Results: A total of 4304 isolates were recovered from 3665 patients. The bacteria species with a prevalence of >5.0% were P. aeruginosa (1030 isolates; 24%), E. coli (747 isolates; 17%), K. pneumoniae (658 isolates; 15%), E. cloacae (376 isolates; 9%), A. baumannii (302 isolates; 7%), and S. marcescens (244 isolates; 6%). The percent susceptible are reported in the table. Most prevalent body sites were respiratory isolates (2,224; 52%), blood isolates (812; 19%), and urine isolates (574; 13%).

Conclusion: In this study, the most common Enterobacteriaceae organisms were E. coli and K. pneumoniae. P. aeruginosa was the predominant Non-Enterobacteriaceae. Amikacin was the most active agent in vitro for P. aeruginosa. Ertapenem, imipenem, and amikacin were the most reliably active drugs in vitro against Enterobacteriaceae.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Subject:
Location: ICC, Munich, Germany
Presentation type:
Back to top