A E Simor

Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada

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Publications (325)1151.15 Total impact

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    ABSTRACT: Rationale: Variability in neonatal vancomycin pharmacokinetics and lack of consensus for optimal trough concentrations in neonatal intensive care units poses challenges to dosing vancomycin in neonates.Objective: To determine vancomycin pharmacokinetics in neonates and evaluate dosing regimens to identify whether practical initial recommendations that targeted trough concentrations most commonly used in neonatal intensive care units could be determined.Methods: Fifty neonates who received vancomycin with at least one set of steady-state levels were evaluated retrospectively. Mean pharmacokinetics were determined using first-order pharmacokinetic equations and Monte Carlo Simulation was used to evaluate initial dosing recommendations for target troughs of 15-20 mg/L, 5-20 mg/L and ≤ 20 mg/L.Results: Monte Carlo Simulation revealed that mg/kg dosing was optimal, where intermittent dosing of 9-12 mg/kg iv q8h had the highest probability of attaining a target trough of 15-20 mg/L. However, continuous infusion with a loading dose of 10mg/kg followed by 25-30 mg/kg/24h had the best overall probability of target attainment. Initial intermittent dosing of 9-15 mg/kg iv q12h was optimal for target troughs of 5-20 mg/L and ≤ 20 mg/L.Conclusions: Practical initial vancomycin dosing of 10mg/kg vancomycin iv q12h or q8h for desired vancomycin troughs of either 5-20mg/L or ≤ 20 mg/L and 15-20mg/L, respectively, were determined. However, due to large interpatient vancomycin pharmacokinetic variability in neonates, monitoring of serum concentrations is recommended when trough concentrations between 15-20mg/L or 5-20mg/L are desired.
    Antimicrobial Agents and Chemotherapy 03/2014; · 4.57 Impact Factor
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    ABSTRACT: Zimbabwe underwent a socioeconomic crisis and resultant increase in food insecurity in 2008-9. The impact of the crisis on Tuberculosis (TB) incidence is unknown. Prospective databases from two mission hospitals, which were geographically widely separated, and remained open during the crisis, were reviewed. At the Howard Hospital (HH) in northern Zimbabwe, TB incidence increased 35% in 2008 from baseline rates in 2003-2007 (p<0.01) and remained at that level in 2009. Murambinda Hospital (MH) in Eastern Zimbabwe also demonstrated a 29% rise in TB incidence from 2007 to 2008 (p<0.01) and remained at that level in 2009. Data collected post-crisis at HH showed a decrease of 33% in TB incidence between 2009 to 2010 (p<0.001) and 2010/2011 TB incidence remained below that of the crisis years of 2008/2009 (p<0.01). Antenatal clinic HIV seroprevalence at HH decreased between 2001(23%) to 2011(11%) (p<0.001). Seasonality of TB incidence was analyzed at both MH and HH. There was a higher TB incidence in the dry season when food is least available (September-November) compared to post harvest (April-June) (p<0.001). This study suggests that an epidemic of TB mirrored socioeconomic collapse and recovery in Zimbabwe. The seasonal data suggests that food security may have been associated with TB incidence both annually and during the crisis in this high HIV prevalence country.
    PLoS ONE 01/2014; 9(2):e83387. · 3.73 Impact Factor
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    ABSTRACT: In 1995, a publicly funded pneumococcal vaccination program for 23-valent polysaccharide vaccine (PPV23) was introduced in Ontario. Conjugate vaccines were authorized in 2001 (PCV7), 2009 (PCV10) and 2010 (PCV13). From 1995-2011, active, population-based surveillance for invasive pneumococcal disease (IPD) was conducted in Metropolitan Toronto and Peel Region, Canada. 6404 IPD cases were included. After PPV23 program implementation in 1995, IPD due to PPV23 strains decreased 49% in older adults prior to PCV7 introduction. Estimated PPV23 efficacy in vaccine eligible adults was 42.2% (95% CI; 28.6-53.2%). IPD incidence due to PCV7 serotypes in children <5 years decreased significantly after PCV7 authorization and before introduction of a publicly funded PCV7 program. Seven years after PCV7 program implementation, the incidence of IPD due to PCV7 serotypes decreased to zero in children and by 88% in adults, however, overall IPD incidence remained unchanged in adults. In 2011, the incidence of IPD was 4.5 per 100,000 in adults aged 15-64 and 19.9 per 100,000 in adults aged over 65 years, with 45 serotypes causing disease. Between 1995 and 2011, the case fatality rate of IPD in adults decreased 2% per year (95% CI, -0.9% to -3.2%). In multivariable analysis, predictors of mortality included older age, chronic conditions, nursing home residence, current smoking, bacteraemia, and illness due to serotypes 3,11A, 19A, and 19F. While vaccination programs resulted in substantial public health benefits, herd immunity benefits of PCV7 were seen at low pediatric vaccination rates, and the case fatality rate of IPD has decreased, IPD will continue to be a cause of considerable morbidity and mortality in adults.
    Vaccine 10/2013; · 3.77 Impact Factor
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    ABSTRACT: The objective was to determine the pharmacokinetics of tobramycin in critically ill adult burn patients and evaluate a variety of milligram per kilogram (mg/kg) total body weight (TBW) regimens to determine whether practical, initial, once-daily administration recommendations to attain desired plasma levels could be identified. A retrospective study was conducted in 58 eligible patients who received tobramycin and had at least one set of steady-state levels from which pharmacokinetic parameters could be determined using standard first-order pharmacokinetic equations. Classification and Regression Tree analysis was used to identify whether tobramycin clearance changed with time postburn. Monte Carlo Simulation was used to evaluate initial mg/kg TBW dosing regimens to determine whether a clinically useful once-daily tobramycin recommendation could be made. Tobramycin clearance was significantly greater for patients ≤45 days postburn vs patients >45 days postburn. Once-daily tobramycin dosing for patients ≤45 days postburn of 10 to 13 mg/kg TBW and for patients >45 days postburn of 8 to 10 mg/kg TBW provided levels similar to those known to be effective in nonburn injury patients. Once-daily tobramycin dosing recommendations for burn patients were determined. Variability in pharmacokinetics in this population and change in pharmacokinetics with time postburn injury necessitate monitoring of tobramycin levels to ensure targets are met and maintained.
    Journal of burn care & research: official publication of the American Burn Association 09/2013; · 1.54 Impact Factor
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    ABSTRACT: Human rhinoviruses (HRVs) are a well-recognized cause of long-term care home (LTCH) outbreaks of respiratory illness. However, there are limited data on the molecular epidemiology of the HRV types involved. To determine whether a large respiratory outbreak in a LTCH was caused by a single type of HRV, and to describe the clinical impact of the outbreak. Nasopharyngeal swabs were collected from residents with one or more of the following: fever, cough, rhinitis, or congestion. Specimens were interrogated by multiplex PCR using the ResPlex II assay. Samples positive for HRV were then submitted for genotyping by partial sequence analysis of the 5' untranslated (UTR) and viral protein (VP) 1 capsid regions. Of 71 screened, 56 residents were positive for a HRV during an outbreak that lasted 5.5 weeks; 27 healthcare workers also had respiratory symptoms. Three residents were transferred to hospital and 2 died. Seven units in two wings of the LTCH were affected, resulting in 3152.5 resident unit closure days. Three different HRV genotypes were identified, although HRV-A1 dominated. This large outbreak of HRVs among residents and healthcare workers in a LTCH was associated with substantial resident and staff morbidity as well as significant unit closures. Multiple types of HRV were implicated but an HRV-A1 type dominated, warranting further investigation into viral determinants for virulence and transmission.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 07/2013; · 3.12 Impact Factor
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    ABSTRACT: Objective. To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile infection (CDI) in Canadian hospitals. Design. National point prevalence survey in November 2010. Setting. Canadian acute care hospitals with at least 50 beds. Patients. Adult inpatients colonized or infected with MRSA or VRE or with CDI. Methods. The prevalence (per 100 inpatients) of MRSA, VRE, and CDI was determined. Associations between prevalence and institutional characteristics and infection control policies were evaluated. Results. One hundred seventy-six hospitals (65% of those eligible) participated. The median (range) prevalence rates for MRSA and VRE colonization or infection and CDI were 4.2% (0%-22.1%), 0.5% (0%-13.1%), and 0.9% (0%-8.6%), respectively. Median MRSA and VRE infection rates were low (0.3% and 0%, respectively). MRSA, VRE, and CDI were thought to have been healthcare associated in 79%, 96%, and 84% of cases, respectively. In multivariable analysis, routine use of a private room for colonized/infected patients was associated with lower median MRSA infection rate (prevalence ratio [PR], 0.44 [95% confidence interval (CI), 0.22-0.88]) and VRE prevalence (PR, 0.26 [95% CI, 0.12-0.57]). Lower VRE rates were also associated with enhanced environmental cleaning (PR, 0.52 [95% CI, 0.36-0.75]). Higher bed occupancy rates were associated with higher rates of CDI (PR, 1.02 [95% CI, 1.01-1.03]). Conclusions. These data provide the first national prevalence estimates for MRSA, VRE, and CDI in Canadian hospitals. Certain infection prevention and control policies were found to be associated with prevalence and deserve further investigation.
    Infection Control and Hospital Epidemiology 07/2013; 34(7):687-93. · 4.02 Impact Factor
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    2nd International Conference on Prevention and Infection Control (ICPIC 2013), Geneva, Switzerland; 06/2013
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    m 2nd International Conference on Prevention and Infection Control (ICPIC 2013), Geneva, Switzerland; 06/2013
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    ABSTRACT: Burn patients are at high risk for infections; however, common indicators of infection are unreliable in this population and can lead to unnecessary use of antibiotics. The study objective was to determine if predictors of early infection in adult acute burn patients are identified to provide clinicians with a practical tool to aid in the diagnosis of infection, thereby minimizing unnecessary exposure to antimicrobials. A retrospective chart review of all adult acute burn injury patients admitted over a 1 year period to the burn centre at Sunnybrook Health Sciences Centre was conducted. Early infection was defined as one that occurred within the first 10 days after injury and in accordance with American Burn Association guidelines. Those without infection were compared to patients with infection generally and also to patients with sepsis specifically. The period prevalence of early infection and sepsis in our patients was 50% (56/111) and 16% (18/111), respectively. It was determined that heart rate ≥110bpm, systolic blood pressure ≤100mmHg and intubation were the best predictors of sepsis (p<0.05); and fraction of inhaled oxygen >25% and maximum temperature ≥39°C were the best predictors of infection (p<0.05). This pilot project identified significant predictors of early infection and sepsis in acute burns and will be validated in a prospective study.
    Burns: journal of the International Society for Burn Injuries 05/2013; · 1.95 Impact Factor
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    ABSTRACT: OBJECTIVES: Vancomycin-resistant enterococci (VRE) can be associated with serious bacteraemia. The focus of this study was to characterize the molecular epidemiology of VRE from bacteraemia cases that were isolated from 1999 to 2009 as part of Canadian Nosocomial Infection Surveillance Program (CNISP) surveillance activities. METHODS: From 1999 to 2009, enterococci were collected from across Canada in accordance with the CNISP VRE surveillance protocol. MICs were determined using broth microdilution. PCR was used to identify vanA, B, C, D, E, G and L genes. Genetic relatedness was examined using multilocus sequence typing (MLST). RESULTS: A total of 128 cases of bacteraemia were reported to CNISP from 1999 to 2009. In 2007, a significant increase in bacteraemia rates was observed in western and central Canada. Eighty-one of the 128 bacteraemia isolates were received for further characterization and were identified as Enterococcus faecium. The majority of isolates were from western Canada (60.5%), followed by central (37.0%) and eastern (2.5%) Canada. Susceptibilities were as follows: daptomycin, linezolid, tigecycline and chloramphenicol, 100%; quinupristin/dalfopristin, 96.3%; high-level gentamicin, 71.6%; tetracycline, 50.6%; high-level streptomycin, 44.4%; rifampicin, 21.0%; nitrofurantoin, 11.1%; clindamycin, 8.6%; ciprofloxacin, levofloxacin and moxifloxacin, 1.2%; and ampicillin, 0.0%. vanA contributed to vancomycin resistance in 90.1% of isolates and vanB in 9.9%. A total of 17 sequence types (STs) were observed. Beginning in 2006 there was a shift in ST from ST16, ST17, ST154 and ST80 to ST18, ST412, ST203 and ST584. CONCLUSIONS: The increase in bacteraemia observed since 2007 in western and central Canada appears to coincide with the shift of MLST STs. All VRE isolates remained susceptible to daptomycin, linezolid, chloramphenicol and tigecycline.
    Journal of Antimicrobial Chemotherapy 03/2013; · 5.34 Impact Factor
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    ABSTRACT: IMPORTANCE Treatment with intravitreal (IVT) injections has increased during the last several years as evidence has accumulated demonstrating the efficacy of anti-vascular endothelial growth factor agents in the treatment of neovascular age-related macular degeneration (AMD) and various retinal vascular diseases. Although IVT injections are generally safe, infectious endophthalmitis is a rare but devastating complication, and the risk of morbidity and vision loss from endophthalmitis is high. OBJECTIVE To examine the change in antibiotic resistance of ocular surface flora with repeated prophylactic use of antibiotics after IVT injection for AMD. DESIGN AND SETTING Prospective, nonrandomized cohort study in 2 tertiary academic hospitals. PARTICIPANTS Patients 65 years and older with newly diagnosed AMD were recruited by 7 retinal specialists from July 1, 2010, through December 31, 2011. INTERVENTION The study group received topical moxifloxacin hydrochloride for 3 days after each monthly IVT injection. MAIN OUTCOME MEASURE Resistance to moxifloxacin and ceftazidime in cultured isolates at baseline and monthly for 3 months by change in minimal inhibitory concentration (MIC) of culture isolates was studied. RESULTS The study group consisted of 84 patients, and the control group had 94 patients. In the study group, the baseline adjusted MIC increased (from 1.04 to 1.25 μg/mL; P = .01) as did the MIC for 50% of isolates (MIC50) (from 0.64 to 1.00 μg/mL) and the MIC for 90% of isolates (MIC90) (from 0.94 to 4.00 μg/mL). In both groups, the culture-positive rate did not change significantly when adjusted for baseline. No significant change was found in the MIC level, culture-positive rate, MIC50 level, and MIC90 level in the control group. Subgroup analysis found diabetes mellitus to be noncontributory to both the MIC and culture-positive rate. No endophthalmitis or adverse events were reported. CONCLUSIONS AND RELEVANCE Repeated use of topical moxifloxacin after IVT injection significantly increases antibiotic resistance of ocular surface flora. We recommend that routine use of prophylactic antibiotics after IVT injection be discouraged. TRIAL REGISTRATION clinicaltrials.gov Identifier:NCT01181713.
    Jama Ophthalmology 02/2013; · 3.83 Impact Factor
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    ABSTRACT: The introduction of commercially available in vitro diagnostic (IVD) PCR assays into the clinical microbiology laboratory has facilitated enhancements to patient care, improving diagnostic sensitivity and specificity (1, 2, 3). Recently, PCR assays for the detection of the Clostridium difficile toxin B gene have become available.…
    Journal of clinical microbiology 01/2013; · 4.16 Impact Factor
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    ABSTRACT: Pulsed-field gel electrophoresis (PFGE) is a valuable molecular typing assay used for methicillin-resistant Staphylococcus aureus (MRSA) surveillance and genotyping. However, there are several limitations associated with PFGE. In Alberta, Canada, the significant increase in the number of MRSA isolates submitted to the Provincial Laboratory for Public Health (ProvLab) for PFGE typing led to the need for an alternative genotyping method. In this study, we describe the transition from PFGE to Staphylococcus protein A (spa), Staphylococcal cassette chromosome (SCCmec), and Panton-Valentine leukocidin (PVL) typing. A total of 1915 clinical MRSA isolates collected from 2005 to 2009 were used to develop and validate an algorithm for assigning PFGE epidemic types using spa, SCCmec, and PVL typing and the resulting data was used to populate a new Alberta MRSA typing database. An additional 12620 clinical MRSA isolates collected from 2010 to 2012 as part of ongoing routine molecular testing at ProvLab were characterized using the new typing algorithm and the Alberta MRSA typing database. Switching to spa, SCCmec, and PVL from PFGE typing substantially reduced hands-on and turn-around times while maintaining historical PFGE epidemic type designations. This led to an approximate $77,000 reduction in costs from 2010 to 2012. PFGE typing is still required for a small subset of MRSA isolates that have spa types that are rare, novel, or associated with more than one PFGE epidemic type.
    PLoS ONE 01/2013; 8(11):e79149. · 3.73 Impact Factor
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    ABSTRACT: MRSA remains a leading cause of hospital-acquired (HAP) and healthcare-associated pneumonia (HCAP). We describe the epidemiology and outcome of MRSA pneumonia in Canadian hospitals, and identify factors contributing to mortality. Prospective surveillance for MRSA pneumonia in adults was done for one year (2011) in 11 Canadian hospitals. Standard criteria for MRSA HAP, HCAP, ventilator-associated pneumonia (VAP), and community-acquired pneumonia (CAP) were used to identify cases. MRSA isolates underwent antimicrobial susceptibility testing, and were characterized by pulsed-field gel electrophoresis (PFGE) and Panton-Valentine leukocidin (PVL) gene detection. The primary outcome was all-cause mortality at 30 days. A multivariable analysis was done to examine the association between various host and microbial factors and mortality. A total of 161 patients with MRSA pneumonia were identified: 90 (56%) with HAP, 26 (16%) HCAP, and 45 (28%) CAP; 23 (14%) patients had VAP. The mean (± SD) incidence of MRSA HAP was 0.32 (± 0.26) per 10,000 patient-days, and of MRSA VAP was 0.30 (± 0.5) per 1,000 ventilator-days. The 30-day all-cause mortality was 28.0%. In multivariable analysis, variables associated with mortality were the presence of multiorgan failure (OR 8.1; 95% CI 2.5-26.0), and infection with an isolate with reduced susceptibility to vancomycin (OR 2.5, 95% CI 1.0-6.3). MRSA pneumonia is associated with significant mortality. Severity of disease at presentation, and infection caused by an isolate with elevated MIC to vancomcyin are associated with increased mortality. Additional studies are required to better understand the impact of host and microbial variables on outcome.
    PLoS ONE 01/2013; 8(9):e75171. · 3.73 Impact Factor
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    ABSTRACT: Design. An analysis of a cluster of New Delhi metallo-β-lactamase-1-producing Klebsiella pneumoniae (NDM1-Kp) and a retrospective case-cohort analysis of risk factors for acquisition in contacts of NDM1-Kp-positive patients. Setting. A 1,100-bed Canadian academic tertiary care center. Patients. Two index patients positive for NDM1-Kp as well as 45 contacts (roommates, ward mates, or environmental contacts) were investigated. Methods. Retrospective chart reviews of all patients colonized or infected with NDM1-Kp as well as contacts of these patients were performed in order to describe the epidemiology and impact of infection prevention and control measures. A case-cohort analysis was conducted investigating 45 contacts of NDM1-Kp-positive patients to determine risk factors for acquisition of NDM1-Kp. Rectal swabs were screened for NDM1-Kp using chromogenic agar. Presence of bla(NDM-1) was confirmed by multiplex polymerase chain reaction. Clonality was assessed with pulsed-field gel electrophoresis (PFGE) using restriction enzyme XbaI. Results. Two index cases carrying NDM1-Kp with different PFGE patterns were identified. Nosocomial transmission to 7 patients (4 roommates, 2 ward mates, and 1 environmental contact) was subsequently identified. Risk factors for acquisition of NDM1-Kp were a history of prior receipt of certain antibiotics (fluoroquinolones [odds ratio (OR), 16.8 (95% confidence interval [CI], 1.30-58.8); [Formula: see text]], trimethoprim-sulfamethoxazole [OR, 11.3 (95% CI, 1.84-70.0); [Formula: see text]], and carbapenems [OR, 16.8 (95% CI, 1.79-157.3); [Formula: see text]]) and duration of exposure to NDM1-Kp-positive roommates (26.5 vs 6.7 days; [Formula: see text]). Conclusion. Two distinct clones of NDM1-Kp were transmitted to 7 inpatient contacts over several months. Implementation of contact precautions, screening of contacts for NDM1-Kp carriage, and attention to environmental disinfection contributed to the interruption of subsequent spread of the organism. The appropriate duration and frequency of screening contacts of NDM1-Kp-positive patients require further study.
    Infection Control and Hospital Epidemiology 01/2013; 34(1):49-55. · 4.02 Impact Factor
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    ABSTRACT: BACKGROUND: This study examined the epidemiology of an outbreak of Staphylococcus aureus surgical site infections (SSI) after cardiovascular surgery, and analyzed risk factors for S aureus SSIs. METHODS: This was a retrospective case-control study to determine risk factors for S aureus SSI in 38 patients who developed S aureus SSI during the outbreak period, compared with age-, sex-, and procedure-matched controls. S aureus strains were typed by pulsed-field gel electrophoresis. RESULTS: A total of 38 patients had S aureus SSI. Pulsed-field gel electrophoresis identified transmission of 3 S aureus clones (2 MSSA clones and 1 MRSA clone). Twenty-one health care workers were carriers of outbreak strains. In multivariate analysis, the significant risk factors for S aureus SSI were previous cardiac surgery (odds ratio, 7.41; 95% confidence interval, 1.05-52.16) and long procedure duration (odds ratio, 1.49; 95% confidence interval, 1.00-2.21). CONCLUSIONS: This outbreak demonstrates evidence of nosocomial transmission of 3 clones of S aureus in the setting of incomplete compliance with recommended standard perioperative infection control measures, associated with a high prevalence of staff carriage of the predominant outbreak strains.
    American journal of infection control 12/2012; · 3.01 Impact Factor
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    ABSTRACT: (See the commentary by Moro, on pages 978-980 .) Infection surveillance definitions for long-term care facilities (ie, the McGeer Criteria) have not been updated since 1991. An expert consensus panel modified these definitions on the basis of a structured review of the literature. Significant changes were made to the criteria defining urinary tract and respiratory tract infections. New definitions were added for norovirus gastroenteritis and Clostridum difficile infections.
    Infection Control and Hospital Epidemiology 10/2012; 33(10):965-77. · 4.02 Impact Factor
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    ABSTRACT: To reduce selective pressure for antimicrobial resistance, empirical use of antipseudomonal antibiotics is often reserved for patients with late-onset hospital-acquired infections. We examined the likelihood of isolating Pseudomonas aeruginosa as a function of time from hospital admission. We conducted a retrospective cohort study of all positive bacterial cultures in a tertiary-care hospital between March 2010 and November 2011. The primary outcome was the proportion of positive cultures yielding P. aeruginosa. Multivariable logistic regression was employed to assess the impact of time from admission on the likelihood of isolating P. aeruginosa, after adjusting for other important risk factors. A total of 7,668 positive cultures were obtained from 4,108 unique patients during the study interval, including 633 (8.3%) yielding P. aeruginosa. The probability of isolating P. aeruginosa increased linearly from 79/2,044 (3.9%) positive cultures obtained on admission to 153/664 (23%) in the 10th week of admission or beyond. The unadjusted odds ratio was 1.002/day (95% confidence interval [CI], 1.0016 to 1.0028; P < 0.0001); the adjusted odds ratio (aOR) was 1.0007/day (95% CI, 1.0001 to 1.0013; P = 0.02). Other important predictors of P. aeruginosa isolation included respiratory specimen type (aOR, 13.8; 95% CI, 9.1 to 21.1), recent hospital admission (aOR,1.8; 95% CI, 1.4 to 2.3), prior P. aeruginosa isolation during current admission (aOR, 4.9; 95% CI, 3.7 to 6.4), and prior antipseudomonal (aOR, 1.9; 95% CI, 1.4 to 2.5) or nonantipseudomonal (aOR, 1.8; 95% CI, 1.4 to 2.4) antibiotic exposure. It was determined that as time from admission increases, there is a linear increase in the likelihood of P. aeruginosa isolation. Any guidelines which distinguish early from late hospital-acquired infection must consider the implications of time point selection on the likelihood of inadequate P. aeruginosa empirical coverage.
    Journal of clinical microbiology 06/2012; 50(8):2695-701. · 4.16 Impact Factor
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    ABSTRACT: Information relating to the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) among hospitalized pediatric patients is limited. This report describes results of national MRSA surveillance among Canadian hospitalized pediatric patients from 1995 to 2007. Surveillance was laboratory-based. Clinical and epidemiologic data were obtained by reviewing the medical records. Standardized definitions were used to determine MRSA infection. Isolates were characterized by pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec typing and antimicrobial susceptibility testing. A total of 1262 pediatric patients were newly identified as MRSA positive from 1995 to 2007. Ages ranged from newborn to 17.9 years, 49% were infected with MRSA (51% colonized), skin and soft tissue infections accounted for the majority (59%) of MRSA infections and 57% were epidemiologically classified as community acquired (CA). The most common epidemic strain types isolated were CMRSA2/USA100/800, CMRSA10/USA300 and CMRSA7/USA400. Overall, MRSA rates per 10,000 patient days increased from 0.08 to 3.88. Since 2005, overall rates of CA-MRSA per 10,000 patient days have dramatically increased while healthcare-associated MRSA rates remained relatively stable. These data suggest that the increase in MRSA among hospitalized pediatric patients is largely driven by the emergence of CA-MRSA strains with skin and soft tissue infections representing the majority of MRSA infections.
    The Pediatric Infectious Disease Journal 05/2012; 31(8):814-20. · 3.57 Impact Factor
  • Canadian Medical Association Journal 04/2012; 184(6):678-9. · 6.47 Impact Factor

Publication Stats

6k Citations
1,151.15 Total Impact Points


  • 1994–2013
    • Sunnybrook Health Sciences Centre
      • • Division of Microbiology
      • • Division of Infectious Diseases
      Toronto, Ontario, Canada
  • 1988–2013
    • University of Toronto
      • • Department of Laboratory Medicine and Pathobiology
      • • Department of Medicine
      • • Sunnybrook Health Sciences Centre
      • • Division of Infectious Diseases
      Toronto, Ontario, Canada
  • 2011
    • University at Buffalo, The State University of New York
      • Department of Pharmaceutical Sciences
      Buffalo, NY, United States
    • McGill University
      Montréal, Quebec, Canada
  • 1988–2011
    • Mount Sinai Hospital, Toronto
      • Department of Microbiology
      Toronto, Ontario, Canada
  • 2010
    • Massachusetts General Hospital
      Boston, Massachusetts, United States
  • 2009–2010
    • University of Guelph
      • Department of Pathobiology
      Guelph, Ontario, Canada
  • 1993–2010
    • National Microbiology Laboratory, Canada
      Winnipeg, Manitoba, Canada
  • 2007–2009
    • Public Health Agency of Canada
      Ottawa, Ontario, Canada
  • 1992–2009
    • University of Manitoba
      Winnipeg, Manitoba, Canada
    • Mount Sinai Hospital
      New York City, New York, United States
  • 2007–2008
    • University Health Network
      • Department of Medicine
      Toronto, Ontario, Canada
  • 2001–2006
    • McMaster University
      • Department of Pathology and Molecular Medicine
      Hamilton, Ontario, Canada
  • 1996–2003
    • SickKids
      • Division of Infectious Diseases
      Toronto, Ontario, Canada
  • 1999
    • The Princess Margaret Hospital
      Toronto, Ontario, Canada
    • Hamilton Health Sciences
      Hamilton, Ontario, Canada