Characterization of Methicillin‐Resistant <i>Staphylococcus aureus</i>, Vancomycin‐Resistant Enterococci and Extended‐Spectrum Beta‐Lactamase‐Producing <i>Escherichia coli</i> in Intensive Care Units in Canada: Results of the Canadian National Intensive Care Unit (Can‐Icu) Study (2005–2006)
Bibliographic record
Abstract
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and vancomycin-resistant enterococci (VRE) are important hospital pathogens in Canada and worldwide. OBJECTIVES: To genotypically and phenotypically characterize the isolates of MRSA, VRE and ESBL-producing E coli collected from patients in Canadian intensive care units (ICUs) in 2005 and 2006. METHODS: Between September 1, 2005, and June 30, 2006, 19 medical centres participating in the Canadian National Intensive Care Unit (CAN-ICU) study collected 4133 unique patient isolates associated with infections in ICUs. Isolates of MRSA underwent mecA polymerase chain reaction (PCR) and Panton-Valentine leukocidin analysis; they were typed using pulsed-field gel electrophoresis. All isolates of E coli with ceftriaxone minimum inhibitory concentrations greater than or equal to 1 mug/mL were tested for the presence of an ESBL using the Clinical Laboratory Standards Institute double-disk diffusion method. Subsequently, PCR and sequence analysis were used to identify bla(SHV), bla(TEM) and bla(CTX-M). Isolates of VRE were tested for the presence of vanA and vanB genes by PCR. RESULTS: Of the 4133 ICU isolates collected, MRSA accounted for 4.7% (193 of 4133) of all isolates. MRSA represented 21.9% (193 of 880) of all S aureus collected during the study; 90.7% were health care-associated MRSA strains and 9.3% were community-associated MRSA strains. Resistance rates for the isolates of MRSA were 91.8% to levofloxacin, 89.9% to clarithromycin, 76.1% to clindamycin and 11.7% to trimethoprim-sulfamethoxazole; no isolates were resistant to vancomycin, linezolid, tigecycline or daptomycin. ESBL-producing E coli accounted for 0.4% (18 of 4133) of all isolates and 3.7% (18 of 493) of E coli isolates. All 18 ESBL-producing E coli were PCR-positive for CTX-M, with bla(CTX-M-15) occurring in 72% (13 of 18) of isolates. All ESBL-producing E coli displayed a multidrug-resistant phenotype (resistant to third-generation cephalosporins and one or more other classes of antimicrobials), with 77.8% of isolates resistant to ciprofloxacin, 55.6% resistant to trimethoprim-sulfamethoxazole, 27.8% resistant to gentamicin and 26.3% resistant to doxycycline; all isolates were susceptible to ertapenem, meropenem and tigecycline. VRE accounted for 0.4% (17 of 4133) of all isolates and 6.7% (17 of 255) of enterococci isolates; 88.2% of VRE had the vanA genotype. Isolated VRE that were tested were uniformly susceptible to linezolid, tigecycline and daptomycin. CONCLUSIONS: MRSA isolated in Canadian ICUs in 2005 and 2006 was predominately health care-associated (90.7%), ESBL-producing E coli were all CTX-M producers (72% bla(CTX-M-15)) and VRE primarily harboured a vanA genotype (88.2%). MRSA, ESBL-producing E coli and VRE were frequently multidrug resistant.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".