Open AccessAntimicrobial-Resistant Pathogens in Intensive Care Units in Canada: Results of the Canadian National Intensive Care Unit (CAN-ICU) Study, 2005-2006
Author(s) -
George G. Zhanel,
Mel DeCorby,
Nancy M. Laing,
Barb Weshnoweski,
Ravi Vashisht,
Franil Tailor,
Kim Nichol,
Aleksandra Wierzbowski,
Patricia J. Baudry,
James A. Karlowsky,
Philippe Lagacé-Wiens,
Andrew Walkty,
Melissa McCracken,
Michael R. Mulvey,
J. Johnson,
Daryl J. Hoban
Publication year - 2008
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.01538-07
Subject(s) - microbiology and biotechnology , linezolid , tigecycline , enterococcus faecium , methicillin resistant staphylococcus aureus , enterococcus , staphylococcus aureus , clindamycin , medicine , intensive care , vancomycin , biology , antimicrobial , antibiotics , intensive care medicine , bacteria , genetics
Between 1 September 2005 and 30 June 2006, 19 medical centers collected 4,180 isolates recovered from clinical specimens from patients in intensive care units (ICUs) in Canada. The 4,180 isolates were collected from 2,292 respiratory specimens (54.8%), 738 blood specimens (17.7%), 581 wound/tissue specimens (13.9%), and 569 urinary specimens (13.6%). The 10 most common organisms isolated from 79.5% of all clinical specimens were methicillin-susceptibleStaphylococcus aureus (MSSA) (16.4%),Escherichia coli (12.8%),Pseudomonas aeruginosa (10.0%),Haemophilus influenzae (7.9%), coagulase-negative staphylococci/Staphylococcus epidermidis (6.5%),Enterococcus spp. (6.1%),Streptococcus pneumoniae (5.8%),Klebsiella pneumoniae (5.8%), methicillin-resistantStaphylococcus aureus (MRSA) (4.7%), andEnterobacter cloacae (3.9%). MRSA made up 22.3% (197/884) of allS. aureus isolates (90.9% of MRSA were health care-associated MRSA, and 9.1% were community-associated MRSA), while vancomycin-resistant enterococci (VRE) made up 6.7% (11/255) of all enterococcal isolates (88.2% of VRE had thevanA genotype). Extended-spectrum β-lactamase (ESBL)-producingE. coli andK. pneumoniae occurred in 3.5% (19/536) and 1.8% (4/224) of isolates, respectively. All 19 ESBL-producingE. coli isolates were PCR positive for CTX-M, withbla CTX-M-15 occurring in 74% (14/19) of isolates. For MRSA, no resistance against daptomycin, linezolid, tigecycline, and vancomycin was observed, while the resistance rates to other agents were as follows: clarithromycin, 89.9%; clindamycin, 76.1%; fluoroquinolones, 90.1 to 91.8%; and trimethoprim-sulfamethoxazole, 11.7%. ForE. coli , no resistance to amikacin, meropenem, and tigecycline was observed, while resistance rates to other agents were as follows: cefazolin, 20.1%; cefepime, 0.7%; ceftriaxone, 3.7%; gentamicin, 3.0%; fluoroquinolones, 21.1%; piperacillin-tazobactam, 1.9%; and trimethoprim-sulfamethoxazole, 24.8%. Resistance rates forP. aeruginosa were as follows: amikacin, 2.6%; cefepime, 10.2%; gentamicin, 15.2%; fluoroquinolones, 23.8 to 25.5%; meropenem, 13.6%; and piperacillin-tazobactam, 9.3%. A multidrug-resistant (MDR) phenotype (resistance to three or more of the following drugs: cefepime, piperacillin-tazobactam, meropenem, amikacin or gentamicin, and ciprofloxacin) occurred frequently inP. aeruginosa (12.6%) but uncommonly inE. coli (0.2%),E. cloacae (0.6%), orK. pneumoniae (0%). In conclusion,S. aureus (MSSA and MRSA),E. coli ,P. aeruginosa ,H. influenzae ,Enterococcus spp.,S. pneumoniae , andK. pneumoniae are the most common isolates recovered from clinical specimens in Canadian ICUs. A MDR phenotype is common forP. aeruginosa isolates in Canadian ICUs.