PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (162)
 

Clipboard (0)
None

Select a Filter Below

Journals
Year of Publication
Document Types
issn:0899-823
1.  Active Surveillance for Carbapenem-Resistant Enterobacteriaceae Using Stool Specimens Submitted for Testing for Clostridium difficile 
Active surveillance to identify asymptomatic carriers of carbapenem-resistant Enterobacteriaceae (CRE) is a recommended strategy for CRE control in healthcare facilities. Active surveillance using stool specimens tested for Clostridium difficile is a relatively low-cost strategy to detect CRE carriers. Further evaluation of this and other risk factor–based active surveillance strategies is warranted.
doi:10.1086/674391
PMCID: PMC3984911  PMID: 24334803
2.  Defining Relatedness in Studies of Transmission of Antimicrobial-Resistant Organisms: Variability in Definitions across Studies and Impact of Different Approaches on Study Conclusions 
OBJECTIVE
Comparison of studies evaluating patient-to-patient transmission of organisms is difficult, given the lack of standardized criteria. We used fluoroquinolone-resistant Escherichia coli (FQREC) as a model to characterize variability in definitions of relatedness across studies and to evaluate the resultant impact on study conclusions.
DESIGN
Narrative review and cohort study.
METHODS
The narrative review compared relatedness criteria across studies of FQREC. Additionally, an existing database was used to compare relatedness of isolates on the basis of molecular criteria alone versus molecular plus clinical criteria with different temporal cutoffs (hospitalization overlap of ≥ 1 day or allowance for nonoverlap of hospitalization dates of ≤7 days or ≤30 days).
RESULTS
Forty-six articles met narrative review inclusion criteria. Sixteen studies exclusively utilized molecular criteria to define relatedness. Thirty studies included molecular and clinical criteria. Of these, 6 included temporal data (ie, time period of isolate identification), 10 included patient location, and 14 included proximity and temporal criteria. For the database analysis, 353 patients were colonized with FQREC. There were 2 main clusters containing 48 and 17 related isolates within 49 pulsed-field gel electrophoresis types. Among the clusters, 18.4% of isolates were related by molecular criteria. Incorporating clinical criteria, fewer isolates were considered related: 5.7% of isolates using 30-day criteria, 3.1% using 7-day criteria, and 1.4% using 1-day overlap.
CONCLUSIONS
There is considerable variability in definitions of relatedness of FQREC. Utilizing molecular criteria alone to define relatedness overestimates transmission compared with definitions including clinical criteria. Standard definitions of relatedness in studies of antimicrobial-resistant organisms are needed.
doi:10.1086/668780
PMCID: PMC3983273  PMID: 23221191
3.  Prior Vancomycin Use Is a Risk Factor for Reduced Vancomycin Susceptibility in Methicillin-Susceptible but Not Methicillin-Resistant Staphylococcus aureus Bacteremia 
OBJECTIVE
Staphylococcus aureus is a cause of community- and healthcare-acquired infections and is associated with substantial morbidity, mortality, and costs. Vancomycin minimum inhibitory concentrations (MICs) among S. aureus have increased, and reduced vancomycin susceptibility (RVS) may be associated with treatment failure. We aimed to identify clinical risk factors for RVS in S. aureus bacteremia.
DESIGN
Case-control.
SETTING
Academic tertiary care medical center and affiliated urban community hospital.
PATIENTS
Cases were patients with RVS S. aureus isolates (defined as vancomycin E-test MIC >1.0 μg/mL). Controls were patients with non-RVS S. aureus isolates.
RESULTS
Of 392 subjects, 134 (34.2%) had RVS. Fifty-eight of 202 patients (28.7%) with methicillin-susceptible S. aureus (MSSA) isolates had RVS, and 76 of 190 patients (40.0%) with methicillin-resistant S. aureus (MRSA) isolates had RVS (P =.02). In unadjusted analyses, prior vancomycin use was associated with RVS (odds ratio [OR], 2.08; 95% confidence interval [CI], 1.00–4.32; P =.046). In stratified analyses, there was significant effect modification by methicillin susceptibility on the association between vancomycin use and RVS (P = .04). In multivariable analyses, after hospital of admission and prior levofloxacin use were controlled for, the association between vancomycin use and RVS was significant for patients with MSSA infection (adjusted OR, 4.02; 95% CI, 1.11–14.50) but not MRSA infection (adjusted OR, 0.87; 95% CI, 0.36–2.13).
CONCLUSIONS
A substantial proportion of patients with S. aureus bacteremia had RVS. The association between prior vancomycin use and RVS was significant for patients with MSSA infection but not MRSA infection, suggesting a complex relationship between the clinical and molecular epidemiology of RVS in S. aureus.
doi:10.1086/663708
PMCID: PMC3983274  PMID: 22227985
4.  Risk Factors for Gastrointestinal Tract Colonization with Extended-Spectrum β-Lactamase (ESBL)–Producing Escherichia coli and Klebsiella Species in Hospitalized Patients 
We describe the prevalence of and risk factors for colonization with extended-spectrum β-lactamase (ESBL)–producing Escherichia coli and Klebsiella species (ESBL-EK) in hospitalized patients. The prevalence of colonization with ESBL-EK was 2.6%. Colonization was associated with cirrhosis, longer duration of hospital stay prior to surveillance, and prior exposure to clindamycin or meropenem.
doi:10.1086/668443
PMCID: PMC3983276  PMID: 23143363
5.  Utility of a Clinical Risk Factor Scoring Model in Predicting Infection with Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae on Hospital Admission 
OBJECTIVE
To validate the utility of a previously published scoring model (Italian) to identify patients infected with community-onset extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-EKP) and develop a new model (Duke) based on local epidemiology.
METHODS
This case-control study included patients 18 years of age or more admitted to Duke University Hospital between January 1, 2008, and December 31, 2010, with culture-confirmed infection due to an ESBL-EKP (cases). Uninfected controls were matched to cases (3 : 1). The Italian model was applied to our patient population for validation. The Duke model was developed through logistic-regression-based prediction scores calculated on variables independently associated with ESBL-EKP isolation. Sensitivities and specificities at various point cutoffs were determined, and determination of the area under the receiver operating characteristic curve (ROC AUC) was performed.
RESULTS
A total of 123 cases and 375 controls were identified. Adjusted odds ratios and 95% confidence intervals for variables previously identified in the Italian model were as follows: hospitalization (3.20 [1.62–6.55]), transfer (4.31 [2.15–8.78]), urinary catheterization (5.92 [3.09–11.60]), β-lactam and/or fluoroquinolone therapy (3.76 [2.06–6.95]), age 70 years or more (1.55 [0.79–3.01]), and Charlson Co-morbidity Score of 4 or above (1.06 [0.55–2.01]). Sensitivity and specificity were, respectively, more than or equal to 95% and less than or equal to 47% for scores 3 or below and were less than or equal to 50% and more than or equal to 96% for scores 8 or above. The ROC AUC was 0.88. Variables identified in the Duke model were as follows: hospitalization (2.63 [1.32–5.41]), transfer (5.30 [2.67–10.71]), urinary catheterization (6.89 [3.62–13.38]), β-lactam and/or fluoroquinolone therapy (3.47 [1.91–6.41]), and immunosuppression (2.34 [1.14–4.80]). Sensitivity and specificity were, respectively, more than or equal to 94% and less than or equal to 65% for scores 3 or below and were less than or equal to 58% and more than or equal to 95% for scores 8 or above. The ROC AUC was 0.89.
CONCLUSION
While the previously reported model was an excellent predictor of community-onset ESBL-EKP infection, models utilizing factors based on local epidemiology may be associated with improved performance.
doi:10.1086/669858
PMCID: PMC3641565  PMID: 23466912
6.  Catheter-Associated Urinary Tract Infection: Does Changing the Definition Change Quality? 
The CDC recently narrowed its definition of catheter-associated urinary tract infection (CAUTI) to exclude asymptomatic bacteriuria. While CAUTI rates declined after the definition changed, rates of related measures remained relatively stagnant, indicating that longitudinal measurements of CAUTI may be misleading and that the definition change itself did not impact care.
doi:10.1086/669525
PMCID: PMC3573527  PMID: 23388369
7.  Central Line–Associated Infections as Defined by the Centers for Medicare and Medicaid Services’ Hospital-Acquired Condition versus Standard Infection Control Surveillance: Why Hospital Compare Seems Conflicted 
OBJECTIVE
To evaluate the concordance of case-finding methods for central line–associated infection as defined by Centers for Medicare and Medicaid Services (CMS) hospital-acquired condition (HAC) compared with traditional infection control (IC) methods.
SETTING
One tertiary care and 2 community hospitals in North Carolina.
PATIENTS
Adult and pediatric hospitalized patients determined to have central line infection by either case-finding method.
METHODS
We performed a retrospective comparative analysis of infection detected using HAC versus standard IC central line–associated bloodstream infection surveillance from October 1, 2007, through December 31, 2009. One billing and 2 IC databases were queried and matched to determine the number and concordance of cases identified by each method. Manual review of 25 cases from each discordant category was performed. Sensitivity and positive predictive value (PPV) were calculated using IC as criterion standard.
RESULTS
A total of 1,505 cases were identified: 844 by International Classification of Diseases, Ninth Revision (ICD-9), and 798 by IC. A total of 204 cases (24%) identified by ICD-9 were deemed not present at hospital admission by coders. Only 112 cases (13%) were concordant. HAC sensitivity was 14% and PPV was 55% compared with IC. Concordance was low regardless of hospital type. Primary reasons for discordance included differences in surveillance and clinical definitions, clinical uncertainty, and poor documentation.
CONCLUSIONS
The case-finding method used by CMS HAC and the methods used for traditional IC surveillance frequently do not agree. This can lead to conflicting results when these 2 measures are used as hospital quality metrics.
doi:10.1086/669527
PMCID: PMC3628677  PMID: 23388357
8.  INFLUENZA VACCINATION IN HEALTHCARE WORKERS: 10-YEAR EXPERIENCE OF A LARGE HEALTHCARE ORGANIZATION 
Objective
To describe the results of different measures implemented to improve compliance with the healthcare worker (HCW) influenza immunization program at BJC HealthCare between 1997 and 2007.
Design
Descriptive retrospective study.
Setting
BJC HealthCare, a 13-hospital nonprofit healthcare organization in the Midwest.
Methods
Review and analysis of HCW influenza vaccination data from all BJC HealthCare Occupational Health Services and hospitals between 1997 and 2007. Occupational health staff, infection prevention personnel and key influenza vaccine campaign leaders were also interviewed regarding implementation measures during the study years.
Results
At the end of 2007, BJC HealthCare had approximately 26,000 employees. Using multiple progressive interventions, influenza vaccination rates among BJC employees increased from 45% in 1997 to 71.9% in 2007 (p<0.001). The influenza vaccination rate in 2007 was significantly higher than in 2006, 71.9% versus 54.2% (p<0.001). Five hospitals had influenza vaccination rates over the target goal of 80% in 2007. The most successful interventions were adding influenza vaccination rates to the incented quality scorecard and declination statements, both implemented in 2007. The most important barriers identified in the interviews related to HCWs’ misconceptions about influenza vaccination and a perceived lack of leadership support.
Conclusions
Influenza vaccination rates in HCWs significantly improved with multiple interventions over the years. However, the BJC HealthCare influenza vaccination target of 80% was not attained at all hospitals with these measures. More aggressive interventions such as implementing mandatory influenza vaccination policies are needed to achieve higher vaccination rates.
doi:10.1086/650449
PMCID: PMC3919446  PMID: 20055666
9.  Predictors and Molecular Epidemiology of Community-Onset Extended-Spectrum β-Lactamase–Producing Escherichia coli Infection in a Midwestern Community 
OBJECTIVE
To identify predictors of community-onset extended-spectrum β-lactamase (ESBL)–producing Escherichia coli infection.
DESIGN
Prospective case-control study.
SETTING
Acute care hospitals and ambulatory clinics in the Chicago, Illinois, region.
PATIENTS
Adults with E. coli clinical isolates cultured in ambulatory settings or within 48 hours of hospital admission.
METHODS
Cases were patients with ESBL-producing E. coli clinical isolates cultured in ambulatory settings or within 48 hours of admission, and controls were patients with non-ESBL-producing E. coli isolates, matched to cases by specimen, location, and date. Clinical variables were ascertained through interviews and medical record review. Molecular methods were used to identify ESBL types, sequence type ST131, and aac(6′)-Ib-cr.
RESULTS
We enrolled 94 cases and 158 controls. Multivariate risk factors for ESBL-producing E. coli infection included travel to India in the past year (odds ratio [OR], 14.40 [95% confidence interval (CI), 2.92–70.95]), ciprofloxacin use (OR, 3.92 [95% CI, 1.90–8.1]), and age (OR, 1.04 [95% CI, 1.02–1.06]). Case isolates exhibited high prevalence of CTX-M-15 (78%), ST131 (50%), and aac(6′)-Ib-cr (66% of isolates with CTX-M-15).
CONCLUSIONS
Providers should be aware of the increased risk of ESBL-producing E. coli infection among returned travelers, especially those from India.
doi:10.1086/671725
PMCID: PMC3916143  PMID: 23917909
10.  Escherichia coli Sequence Type 131 Is a Dominant, Antimicrobial-Resistant Clonal Group Associated with Healthcare and Elderly Hosts 
OBJECTIVE
To determine prevalence, predictors, and outcomes of infection due to Escherichia coli sequence type ST131.
DESIGN
Retrospective cohort.
SETTING
All healthcare settings in Olmsted County, Minnesota (eg, community hospital, tertiary care center, long-term care facilities, and ambulatory clinics).
PATIENTS
Ambulatory and hospitalized children and adults with extraintestinal E. coli isolates.
METHODS
We analyzed 299 consecutive, nonduplicate extraintestinal E. coli isolates submitted to Olmsted County laboratories in February and March 2011. ST131 was identified using single-nucleotide polymorphism polymerase chain reaction and further evaluated through pulsed-field gel electrophoresis. Associated clinical data were abstracted through medical record review.
RESULTS
Most isolates were from urine specimens (90%), outpatients (68%), and community-associated infections (61%). ST131 accounted for 27% of isolates overall and for a larger proportion of those isolates resistant to fluoroquinolones (81%), trimethoprim-sulfamethoxazole (42%), gentamicin (79%), and ceftriaxone (50%). The prevalence of ST131 increased with age (accounting for 5% of isolates from those 11–20 years of age, 26% of isolates from those 51–60 years of age, and 50% of isolates from those 91–100 years of age). ST131 accounted for a greater proportion of healthcare-associated isolates (49%) than community-associated isolates (15%) and for fully 76% of E. coli isolates from long-term care facility (LTCF) residents. Multivariable predictors of ST131 carriage included older age, LTCF residence, previous urinary tract infection, high-complexity infection, and previous use of fluoroquinolones, macrolides, and extended-spectrum cephalosporins. With multivariable adjustment, ST131-associated infection outcomes included receipt of more than 1 antibiotic (odds ratio [OR], 2.54 [95% confidence interval (CI), 1.25–5.17]) and persistent or recurrent symptoms (OR, 2.53 [95% CI, 1.08–5.96]). Two globally predominant ST131 pulsotypes accounted for 45% of ST131 isolates.
CONCLUSIONS
ST131 is a dominant, antimicrobial-resistant clonal group associated with healthcare settings, elderly hosts, and persistent or recurrent symptoms.
doi:10.1086/669865
PMCID: PMC3916146  PMID: 23466908
11.  Observing and Improving Hand Hygiene Compliance: Implementation and Refinement of an Electronic-Assisted Direct-Observer Hand Hygiene Audit Program 
We implemented a direct-observer hand hygiene audit program that used trained observers, wireless data entry devices, and an intranet portal. We improved the reliability and utility of the data by standardizing audit processes, regularly retraining auditors, developing an audit guidance tool, and reporting weighted composite hand hygiene compliance scores.
doi:10.1086/669084
PMCID: PMC3622086  PMID: 23295569
12.  Quantifying The Impact of Extra-Nasal Testing Body Sites for MRSA Colonization at the Time of Hospital or Intensive Care Unit Admission 
Objective
Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of healthcare-associated infections. Recent legislative mandates require nares screening for MRSA at hospital and ICU admission in many states. However, MRSA colonization at extra-nasal sites is increasingly recognized. We conducted a systematic review of the literature to identify the yield of extra-nasal testing for MRSA.
Design
We searched MEDLINE from January 1966 through January 2012 for articles comparing nasal and extra-nasal screening for MRSA colonization. Studies were categorized by population tested, specifically those admitted to ICUs, and those admitted to hospitals with a high prevalence (≥6%) or low prevalence (<6%) of MRSA carriers. Data were extracted using a standardized instrument.
Results
We reviewed 4,381 abstracts and 735 manuscripts. Twenty-three manuscripts met criteria for analysis (n=39,479 patients). Extra-nasal MRSA screening increased yield by approximately one-third over nares alone. The yield was similar upon ICU admission (weighted average 33%, range 9%–69%), and hospital admission in high (weighted average 37%, range 9–86%) and low prevalence (weighted average 50%, range 0–150%) populations. Comparing individual extra nasal sites, testing the oropharynx increased MRSA detection by 21% over nares alone; rectum by 20%; wounds by 17%; and axilla by 7%.
Conclusions
Extra-nasal MRSA screening at hospital or ICU admission in adults will increase MRSA detection by one-third compared to nares screening alone. Findings were consistent among subpopulations examined. Extra-nasal testing may be a valuable strategy for outbreak control or in settings of persistent disease, particularly when combined with decolonization or enhanced infection prevention protocols.
doi:10.1086/669095
PMCID: PMC3894230  PMID: 23295562
13.  Prevalence and Predictors of Compliance with Discontinuation of Airborne Isolation in Patients with Suspected Pulmonary Tuberculosis 
OBJECTIVE
Examine the use of airborne isolation by identifying reasons for nontimely discontinuation and predictors of compliance with Centers for Disease Control and Prevention (CDC) guidelines. Compliance with guidelines should result in timely (within 48 hours) discontinuation of isolation in patients without infectious pulmonary tuberculosis (TB).
DESIGN
Retrospective, observational study.
SETTING
A private, university-affiliated, tertiary-care medical center.
PATIENTS
All patients in airborne isolation for suspected pulmonary TB from June through December 2011.
METHOD
Chart reviews were performed to identify airborne isolation practices and delayed (greater than 48 hours) or very delayed (greater than 72 hours) discontinuation. We used descriptive statistics and logistic regression to determine independent predictors of nontimely discontinuation of isolation.
RESULTS
We identified 113 patients (mean age ± standard deviation, 59.8 ± 17.7 years; male sex, 75.2%; white race, 15.9%; mean collection interval ± standard deviation, 21.4 ± 12.9 hours). Delayed and very delayed isolation discontinuation was noted in 81% and 49% of patients, respectively. No significant differences in demographic characteristics and clinical characteristics were identified between groups. Predictors of timely (within 48 hours) airborne isolation discontinuation included use of alternate diagnosis for discontinuation of isolation (P = .02), early infectious diseases (ID) consultation (P = .03), pulmonary consultation (P = .02), average sputum collection interval less than 24 hours (P = .03), and need for more than 1 induced sputum specimen (P = .05). Adjusting for potential confounders, pulmonary consultation (odds ratio [OR] [95% confidence interval (CI)], 0.14 [0.03–0.58]), alternate diagnosis for discontinuation of isolation (OR [95% CI], 4.5 [1.3–15.8]), and early ID consultation (OR [95% CI], 4.0 [1.1–14.8]) were independently associated with timely discontinuation.
CONCLUSIONS
Timely airborne isolation discontinuation occurs in only 18.6% of cases and is an opportunity for cost savings, improved efficiency, and potentially patient safety and satisfaction.
doi:10.1086/671732
PMCID: PMC3882086  PMID: 23917912
14.  Association of Vancomycin-Resistant Enterococcus Bacteremia and Ceftriaxone Usage 
Objective
Vancomycin-resistant Enterococci (VRE) have become a public health concern with implications for patient mortality and costs. Hospital antibiotic usage may impact VRE incidence, but the relationship is poorly understood. Animal investigations suggest ceftriaxone may be associated with VRE proliferation. We measured antimicrobial usage and VRE bloodstream infection (BSI) incidence to test our hypothesis that increased ceftriaxone use would be associated with a higher incidence of VRE-BSI.
Setting
The University of Alabama at Birmingham Medical Center is a 900-bed urban tertiary-care hospital
Methods
Retrospective analysis of antimicrobial usage and VRE-BSI from 2005 to 2008 (43 months). Antimicrobial usage quantified as days of therapy/1,000 patient-days (DOT). VRE-BSI incidence calculated as cases/1,000 patient-days. Negative binomial regression with adjustment for correlation between consecutive observations measured the association between antimicrobial usage and VRE-BSI incidence at the hospital- and care-unit levels.
Results
VRE-BSI incidence increased from 0.06 to 0.17 infections/1,000 patient-days. Hospital VRE-BSI incidence was associated with prior-month ceftriaxone DOT (Incidence Rate Ratio 1.38 per 10 DOT; p=0.005). After controlling for ceftriaxone, prior-month cephalosporin use (class) was not predictive of VRE-BSI (p=0.70). Similarly, prior-month use of piperacillin-tazobactam, ceftazidime, cefepime, cefazolin, or vancomycin was not predictive of VRE-BSI when considered individually (p≥0.4 for all comparisons). The final model suggests that type of intensive care unit was related to VRE-BSI incidence.
Conclusions
Ceftriaxone use in the prior month, but not cephalosporin (class) or vancomycin use, was related to VRE-BSI incidence. These findings suggest that an antimicrobial stewardship program that limits ceftriaxone may reduce nosocomial VRE-BSI incidence.
doi:10.1086/666331
PMCID: PMC3879097  PMID: 22669234
15.  Central Line–Associated Bloodstream Infections in Adult Hematology Patients with Febrile Neutropenia: An Evaluation of Surveillance Definitions Using Differential Time to Blood Culture Positivity 
We used differential time to positivity between central and peripheral blood cultures to evaluate the positive predictive value (PPV) of the National Healthcare Safety Network central line–associated bloodstream infection (CLABSI) surveillance definition among hematology patients with febrile neutropenia. The PPV was 27.7%, which suggests that, when the definition is applied to this population, CLABSI rates will be substantially overestimated.
doi:10.1086/668431
PMCID: PMC3628695  PMID: 23221198
16.  High frequency of multi drug resistant Gram-negative rods in two neonatal intensive care units in the Philippines 
Background
Though hospital-acquired infections appear to be a growing threat to newborn survival in the developing world, the epidemiology of this problem remains poorly characterized.
Methods
Over a 10 month period, we conducted prospective longitudinal surveillance for colonization and bloodstream infections with Gram-negative rods (GNRs) among all infants admitted to the two largest neonatal intensive care units (NICUs) in Manila, the Philippines, determined antibiotic sensitivities, and calculated adjusted odds ratios (OR) for factors for bacteremia using multivariate logistic regression.
Results
Among 1,831 neonates enrolled over a 10-month period, 1017 (55%) became newly colonized and 358 (19.6%) became bacteremic with a resistant GNR, most commonly Klebsiella species, Enterobacter species, Acinetobacter species, and Pseudomonas aeruginosa. The proportion of invasive isolates with antibiotic resistance was: imipenem 20%, trimethoprim-sulfamethoxazole 41%, amikacin 52%, ampicillin/sulbactam 63%, ceftazidime 67%, and tobramycin 80%. Factors significantly associated with increased risk of bacteremia were mechanical ventilation and prematurity. Additionally, colonization with a resistant GNR was an independent risk for bacteremia. (OR 1.4, 95% CI 1.0 – 1.9)
Conclusions
Colonization with a resistant GNR was an independent risk factor for sepsis. If our data are typical, the unusually high intensity of colonization pressure and disease with multidrug-resistant GNRs at these two NICUs constitutes an emerging health care crisis in the developing world. Improved infection control methods are therefore critically needed in developing country settings.
doi:10.1086/597512
PMCID: PMC3857697  PMID: 19435448
18.  The precision of human-generated-hand-hygiene observations: a comparison of human observation with an automated monitoring system 
We compared nearly 1400 hand-hygiene-related events observed by an automated system and by human observations. The records differed for 38% of these events. Two likely explanations for the inconsistencies were the distance between the observer and the event and the busyness of the clinic.
doi:10.1086/668426
PMCID: PMC3632323  PMID: 23143367
19.  INCIDENCE, SECULAR TRENDS AND OUTCOMES OF PROSTHETIC JOINT INFECTION (PJI): A POPULATION BASED STUDY, OLMSTED COUNTY, MINNESOTA, 1969 – 2007 
Context
The epidemiology of prosthetic joint infection (PJI) in a population based cohort has not been studied in the United States.
Objectives
To provide an accurate assessment of the true incidence, secular trends, clinical manifestations, microbiology and treatment outcomes of PJI in a population based cohort.
Design
Historical cohort study
Setting
Olmsted County, Minnesota, United States of America.
Participants
Residents who underwent total knee arthroplasty (TKA) or total hip arthroplasty (THA) between 1/ 1/ 1969 and 12/ 31/ 2007.
Methods
Incidence rates and trends in PJI were assessed using the Kaplan Meier method and log-rank test, as were treatment outcomes among PJI cases.
Results
7375 THA or TKA were implanted in residents of Olmsted County during the study period. Seventy five discrete joints in 70 individuals developed PJI, during a mean(+/− SD) follow up of 6.8 (+/− 6.1) years. The cumulative incidence of PJI was 0.5%, 0.8% and 1.4% after 1, 5 and 10 years following arthroplasty, respectively. Overall, the rate of survival free of clinical failure after treatment of PJI was 76.8 % ( 95% CI: 64.3 – 85.2) and 65.2 % ( 95% CI: 33.1 – 76.2) at 3 years and 5 years, respectively. The incidence and treatment outcomes did not significantly differ by decade of implantation, patient age at implantation, gender or joint location.
Conclusions
The incidence of PJI is relatively low in a population based cohort, and is a function of age of the prosthesis. Incidence trends and outcomes have not significantly changed over the past forty years.
doi:10.1086/668421
PMCID: PMC3602045  PMID: 23143357
20.  Systematic Review and Cost Analysis Comparing Use of Chlorhexidine with Use of Iodine for Preoperative Skin Antisepsis to Prevent Surgical Site Infection 
Objective
To compare use of chlorhexidine with use of iodine for preoperative skin antisepsis with respect to effectiveness in preventing surgical site infections (SSIs) and cost.
Methods
We searched the Agency for Healthcare Research and Quality website, the Cochrane Library, Medline, and EMBASE up to January 2010 for eligible studies. Included studies were systematic reviews, meta-analyses, or randomized controlled trials (RCTs) comparing preoperative skin antisepsis with chlorhexidine and with iodine and assessing for the outcomes of SSI or positive skin culture result after application. One reviewer extracted data and assessed individual study quality, quality of evidence for each outcome, and publication bias. Meta-analyses were performed using a fixed-effects model. Using results from the meta-analysis and cost data from the Hospital of the University of Pennsylvania, we developed a decision analytic cost-benefit model to compare the economic value, from the hospital perspective, of antisepsis with iodine versus antisepsis with 2 preparations of chlorhexidine (ie, 4% chlorhexidine bottle and single-use applicators of a 2% chlorhexidine gluconate [CHG] and 70% isopropyl alcohol [IPA] solution), and also performed sensitivity analyses.
Results
Nine RCTs with a total of 3,614 patients were included in the meta-analysis. Meta-analysis revealed that chlorhexidine antisepsis was associated with significantly fewer SSIs (adjusted risk ratio, 0.64 [95% confidence interval, [0.51–0.80]) and positive skin culture results (adjusted risk ratio, 0.44 [95% confidence interval, 0.35–0.56]) than was iodine antisepsis. In the cost-benefit model baseline scenario, switching from iodine to chlorhexidine resulted in a net cost savings of $16–$26 per surgical case and $349,904–$568,594 per year for the Hospital of the University of Pennsylvania. Sensitivity analyses showed that net cost savings persisted under most circumstances.
Conclusions
Preoperative skin antisepsis with chlorhexidine is more effective than preoperative skin antisepsis with iodine for preventing SSI and results in cost savings.
doi:10.1086/657134
PMCID: PMC3833867  PMID: 20969449
21.  Antibiotic Resistance in Non-Major Metropolitan Skilled Nursing Facilities: Prevalence and Inter-Facility Variation 
doi:10.1086/668018
PMCID: PMC3557526  PMID: 23041821
antibiotic resistance; methicillin-resistant Staphylococcus aureus; fluoroquinolone resistance; nursing home; long-term care
23.  Predictors of Hospital-Acquired Urinary Tract-Related Bloodstream Infection 
Objective
Bloodstream infection (BSI) secondary to nosocomial urinary tract infection (UTI) is associated with substantial morbidity, mortality and additional financial costs. Our objective was to identify predictors of nosocomial urinary tract-related BSI.
Design
Matched case-control study.
Setting
Midwestern tertiary care hospital.
Patients
Cases (n = 298) were patients with a positive urine culture obtained > 48 hours after admission and a blood culture obtained within 14 days of the urine culture which grew the same organism. Controls (n = 667), selected by incidence density sampling, included patients with a positive urine culture who were at risk for BSI but did not develop one.
Methods
Conditional logistic regression and classification and regression tree (CART) analyses.
Results
The most frequently isolated microorganisms which spread from the urinary tract to the bloodstream were Enterococcus sp. Independent risk factors included neutropenia (OR = 10.99, 95% CI: 5.78–20.88), renal disease (OR = 2.96, 95% CI: 1.98–4.41) and male sex (OR = 2.18, 95% CI: 1.52–3.12). The probability of developing a urinary tract-related BSI among neutropenic patients was 70%. Receipt of immunosuppressants (OR = 1.53, 95% CI: 1.04–2.25), insulin (OR=4.82, 95% CI: 2.52–9.21) and antibacterials (OR = 0.66, 95% CI: 0.44–0.97) also significantly altered risk.
Conclusions
The heightened risk of urinary tract-related BSI associated with several comorbid conditions suggests that the management of nosocomial bacteriuria may benefit from tailoring to certain patient subgroups. Consideration of time-dependent risk factors such as medications may also help guide clinical decisions in reducing BSI.
doi:10.1086/667731
PMCID: PMC3442945  PMID: 22961019
24.  Surveillance Definitions of Infections in Long-Term Care Facilities: Revisiting the McGeer Criteria 
(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.
doi:10.1086/667743
PMCID: PMC3538836  PMID: 22961014
25.  Lack of Seasonality in the Occurrence of Multidrug-Resistant Acinectobacter baumannii Complex 
doi:10.1086/667741
PMCID: PMC3601442  PMID: 22961027
Acinetobacter baumannii; multidrug resistance; antimicrobial susceptibility; epidemiology; seasonality

Results 1-25 (162)