Despite agreement that handwashing decreases hospital-acquired infections (HAIs), physician hand hygiene remains suboptimal. Interventions to empower patients to discuss handwashing have had variable success.

To understand patient perceived barriers to discussing physician hand hygiene and to determine whether patients prefer electronic alerts over printed information as an intervention to discuss physician handwashing.

Cross-sectional study of 250 medical/surgical patients at an academic medical center.

Ninety-six percent of patients had heard of HAIs. Ninety-six percent of patients thought it was important for physicians to clean their hands before touching anything in a patient's room. The majority of patients (78%) believed patients should remind physicians to clean their hands. Thirty-two percent of patients observed physician hand hygiene noncompliance. In multivariate analysis, predictors of not speaking up regarding physician hand hygiene included never having worked in health care (odds ratio [OR], 2.8 [95% confidence interval (CI), 1.5-5.1]), not observing a physician clean hands before touching the patient (OR, 2.4 [95% CI, 1.3-4.4]), and not thinking patients should have to remind physicians to clean hands (OR, 5.5 [95% CI, 2.4-12.7]). Ninety-three percent of patients favored electronic device reminders over printed information as an intervention to encourage patients to discuss hand hygiene with their doctors.

The strongest predictor of not challenging a doctor to clean their hands was not believing it was the patient's role to do so. Patients prefer electronic device reminders to printed information as an aid in overcoming barriers to discussing hand hygiene with physicians.

Infections due to fluoroquinolone-resistant Escherichia coli (FQREC) are associated with significant morbidity and mortality. Fluoroquinolone resistance likely arises at the level of gastrointestinal colonization. The objective of this study was to identify risk factors for the development of FQREC gastrointestinal tract colonization in hospitalized patients, including the impact of antibiotics prescribed during hospitalization.

A prospective cohort study was conducted from 2002 to 2004 within a university health system.

Hospitalized patients initially colonized with fluoroquinolone-susceptible E. coli were followed up with serial fecal sampling for new FQREC colonization or until hospital discharge or death. A Cox proportional hazards regression model was developed to identify risk factors for new FQREC colonization, with antibiotic exposure modeled as time-varying covariates.

Of 395 subjects, 73 (18.5%) became newly colonized with FQREC. Length of stay before sampling (hazard ratio [HR], 1.02 [95% confidence interval (CI), 1.1–1.03]; P = .003) and malignancy (HR, 0.37 [95% CI, 0.21–0.67]; P = .001) were significantly associated with the development of FQREC colonization. In addition, receipt of a first-generation cephalosporin (HR, 1.19 [95% CI, 1.10–1.29]; P<.001) or cefepime (HR, 1.05 [95% CI, 1.00–1.10]; P = .048) during hospitalization increased the risk of new FQREC colonization.

The acquisition of FQREC in the hospital setting is complex, and antimicrobial stewardship programs should take into account patterns of antibiotic use in implementing strategies to reduce the development of new FQREC colonization. Future studies are needed to identify risk factors for infection in hospitalized patients newly colonized with FQREC.

Multidrug-resistant Enterobacteriaceae pose a serious infection control challenge and have emerged as a public health threat. We examined national trends in the proportion of Klebsiella pneumoniae isolates resistant to carbapenems (CRKP) and third-generation cephalosporins (G3CRKP).

Retrospective analysis of approximately 500,000 K. pneumoniae isolates cultured between January 1999 and July 2010 at 287 clinical laboratories throughout the United States.

Isolates were defined as CRKP if they were nonsusceptible to 1 or more carbapenems and were defined as G3CRKP if they were nonsusceptible to ceftazidime, ceftriaxone, or related antibiotics. A multivariable analysis examined trends in the proportion of resistant isolates, adjusting for age, sex, isolate source, patient location, and geographic region.

The crude proportion of CRKP increased from less than 0.1% to 4.5% between 2002 and 2010; the frequency of G3CRKP increased from 5.3% to 11.5% between 1999 and 2010. G3CRKP and CRKP were more common among elderly patients (those greater than 65 years of age); the adjusted odds ratio (aOR) relative to pediatric patients (those less than 18 years of age) was 1.2 for G3CRKP (95% confidence interval [CI], 1.2–1.3) and 3.3 for CRKP (95% CI, 2.6–4.2). G3CRKP and CRKP were also more common among patients from the northeastern United States (aOR, 2.9 [95% CI, 2.8–3.0] and 9.0 [95% CI, 7.9–10.4]) than among those from the western United States. The prevalence of outpatient CRKP isolates increased after 2006, reaching 1.9% of isolates in our sample in 2010 (95% CI, 1.6%–2.1%).

The frequency of G3CRKP and CRKP is increasing in all regions of the United States, and resistance is emerging among isolates recovered in the outpatient setting. This underscores the need for enhanced laboratory capacity and coordinated surveillance strategies to contain the further spread of these emerging pathogens.

Healthcare-acquired infections (HAIs) cause substantial patient morbidity and mortality. Items in the environment harbor microorganisms that may contribute to HAIs. Reduction in surface bioburden may be an effective strategy to reduce HAIs. The inherent biocidal properties of copper surfaces offer a theoretical advantage to conventional cleaning, as the effect is continuous rather than episodic. We sought to determine whether placement of copper alloy-surfaced objects in an intensive care unit (ICU) reduced the risk of HAI.

Intention-to-treat randomized control trial between July 12, 2010, and June 14, 2011.

The ICUs of 3 hospitals.

Patients presenting for admission to the ICU.

Patients were randomly placed in available rooms with or without copper alloy surfaces, and the rates of incident HAI and/or colonization with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) in each type of room were compared.

The rate of HAI and/or MRSA or VRE colonization in ICU rooms with copper alloy surfaces was significantly lower than that in standard ICU rooms (0.071 vs 0.123; P = .020). For HAI only, the rate was reduced from 0.081 to 0.034 (P = .013).

Patients cared for in ICU rooms with copper alloy surfaces had a significantly lower rate of incident HAI and/or colonization with MRSA or VRE than did patients treated in standard rooms. Additional studies are needed to determine the clinical effect of copper alloy surfaces in additional patient populations and settings.

Describe the epidemiology of central line-associated bloodstream infections (CLABSIs) in neonatal intensive care units (NICUs) participating in a standardized and mandatory CLABSI surveillance program.

Retrospective cohort.

We included patients admitted (April 2007-March 2011) to 7 level II/III NICUs who developed a CLABSI (as defined by the National Healthcare Safety Network).

. CLABSIs/1,000 central line–days and device utilization ratio were calculated; x2 test, Student t test, Kruskal-Wallis, and Poisson regression were used.

Overall, 191 patients had 202 CLABSI episodes for a pooled mean rate of 4.0 CLABSIs/1,000 central line-days and a device utilization ratio of 0.20. Annual pooled mean CLABSI rates increased from 3.6 in 2007-2008 to 5.1 CLABSIs/1,000 central line-days in 2010-2011 (P = .01). The all-cause 30-day case fatality proportion was 8.9% (n = 17) and occurred a median of 8 days after CLABSI. Coagulase-negative Staphylococcus was identified in 112 (50.5%) cases. Staphylococcus aureus was identified in 22 cases, and 3 (13.6%) were resistant to methicillin. An underlying intra-abdominal pathology was found in 20% (40/202) of CLABSI cases, 50% of which were reported in the last year of study. When adjusted for mean birth weight, annual CLABSI incidence rates were independently associated with the proportion of intra-abdominal pathology (P = .007) and the proportion of pulmonary pathology (P = .016) reported.

The increase in CLABSI rates in Quebec NICUs seems to be associated with an increased proportion of cases with underlying intra-abdominal and pulmonary pathologies, which needs further investigation.

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.

Narrative review and cohort study.

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).

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.

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.

To summarize the approaches used to manage exposure of patients to inadequately sterilized neurosurgical instruments contaminated as a result of Creutzfeldt-Jakob disease (CJD).

Information on past CJD exposure incidents reported to the Centers for Disease Control and Prevention (CDC) was aggregated and summarized. In addition, inactivation studies were reviewed, and data from selected publications were provided for reference.

Nineteen incidents of patient exposure to potentially CJD-contaminated instruments were reported to the CDC, including 17 that involved intracranial procedures and 2 that involved ophthalmologic procedures. In more than 50% of incidents, the neurosurgical procedures were performed for diagnostic work up of the index patients. At least 12 of the hospitals had multiple neurosurgical sets, and the CJD-contaminated instruments could not be identified in 11 of 19 hospitals. In 12 of 15 hospitals with neurosurgical incidents, a decision was made to notify patients of their potential exposure.

Neurosurgical instruments used for treatment of patients with suspected or diagnosed CJD or patients whose diagnosis is unclear should be promptly identified and sterilized using recommended CJD decontamination protocols. Inability to trace instruments complicates appropriate management of exposure incidents. The feasibility of instituting instrument tracking procedures should be considered.

We sought to identify hospital characteristics associated with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) carriage among inpatients.

Prospective cohort study.

Orange County, California.

Thirty hospitals in a single county.

We collected clinical MRSA isolates from inpatients in 30 of 31 hospitals in Orange County, California, from October 2008 through April 2010. We characterized isolates by spa typing to identify CA-MRSA strains. Using California's mandatory hospitalization data set, we identified hospital-level predictors of CA-MRSA isolation.

CA-MRSA strains represented 1,033 (46%) of 2,246 of MRSA isolates. By hospital, the median percentage of CA-MRSA isolates was 46% (range, 14%–81%). In multivariate models, CA-MRSA isolation was associated with smaller hospitals (odds ratio [OR], 0.97, or 3% decreased odds of CA-MRSA isolation per 1,000 annual admissions; P<.001), hospitals with more Medicaid-insured patients (OR, 1.2; P = .002), and hospitals with more patients with low comorbidity scores (OR, 1.3; P< .001). Results were similar when restricted to isolates from patients with hospital-onset infection.

Among 30 hospitals, CA-MRSA comprised nearly half of MRSA isolates. There was substantial variability in CA-MRSA penetration across hospitals, with more CA-MRSA in smaller hospitals with healthier but socially disadvantaged patient populations. Additional research is needed to determine whether infection control strategies can be successful in targeting CA-MRSA influx.

To obtain an unbiased estimate of the excess hospital length of stay (LOS) and cost attributable to extended-spectrum β-lactamase (ESBL) positivity in bloodstream infections (BSIs) due to Enterobacteriaceae.

Retrospective cohort study.

A 2,200-bed academic medical center in Geneva, Switzerland.

Patients admitted during 2009.

We used multistate modeling and Cox proportional hazards models to determine the excess LOS and adjusted end-of-LOS hazard ratio (HR) for ESBL-positive and ESBL-negative BSI. We estimated economic burden as the product of excess LOS and average bed-day cost. Patient-level accounting data provided a complementary analysis of economic burden. A predictive model was fitted to national surveillance data.

Thirty ESBL-positive and 96 ESBL-negative BSI cases were included. The excess LOS attributable to ESBL-positive and ESBL-negative BSI was 9.4 (95% confidence interval [CI], 0.4–18.4) and 2.6 (95% CI, 0.7–5.9) days, respectively. ESBL positivity was therefore associated with 6.8 excess days and CHF 9,473 per BSI. The adjusted end-of-LOS HRs for ESBL-positive and ESBL-negative BSI were 0.62 (95% CI, 0.43–0.89) and 0.90 (95% CI, 0.74–1.10), respectively. After reimbursement, the average financial loss per acute care episode in ESBL-positive BSI, ESBL-negative BSI, and control cohorts was CHF 48,674, 48,131, and 13,532, respectively. Our predictive model estimated that the nationwide cost of third-generation cephalosporin resistance would increase from CHF 2,084,000 in 2010 to CHF 3,526,000 in 2015.

This is the first hospital-wide analysis of excess LOS attributable to ESBL positivity determined using multistate modeling to avoid time-dependent bias. These results may inform health-economic evaluations of interventions targeting ESBL control.

To investigate prospectively the clinical course and risk factors for ventilator-associated tracheobronchitis (VAT) and the impact of VAT on intensive care unit (ICU) morbidity and mortality.

Prospective cohort study.

University Hospital Larissa, Larissa, Greece

Critical care patients who received mechanical ventilation for more than 48 hours were prospectively studied between 2009 and 2011.

The modified Clinical Pulmonary Infection Score, white blood cell count, and C-reactive protein level were systematically assessed every 2 days for the first 2 weeks of ICU stay. Bronchial secretions were assessed daily. Quantitative cultures of endotracheal secretions were performed on the first ICU day for every patient and every 2 days thereafter for the first 2 weeks or more at the discretion of the attending physicians. Definition of VAT was based on previously published criteria.

A total of 236 patients were observed; 42 patients (18%) presented with VAT. Gram-negative pathogens, which were usually multidrug resistant, were responsible for 92.9% of cases. Patients with a neurosurgical admission presented with VAT significantly more often than did other ICU patients (28.5% vs 14.1%; P = .02). The occurrence of VAT was a significant risk factor for increased duration of ICU stay (OR [95% CI], 3.04 [1.35-6.85]; P = .01). Age (OR [95% CI], 1.04 [1.015-1.06]; P = .02), Acute Physiology and Chronic Health Evaluation II score (OR [95% CI], 1.08 [1.015-1.16]; P = .02), and C-reactive protein level at admission (OR [95% CI], 1.05 [1.011.1]; P = .02) were independent factors for ICU mortality.

VAT is a nosocomial infection that might be associated with prolonged stay in the ICU, especially in neurocritical patients. VAT was not associated with increased mortality in our study.

To assess the impact of an electronic surveillance system on isolation practices and rates of methicillin-resistant Staphylococcus aureus (MRSA).

A pre-post test intervention.

Inpatient units (except psychiatry and labor and delivery) in 4 New York City hospitals.

All patients for whom isolation precautions were indicated, May 2009–December 2011.

Trained observers assessed isolation sign postings, availability of isolation carts, and staff use of personal protective equipment (PPE). Infection rates were obtained from the infection control department. Regression analyses were used to examine the association between the surveillance system, infection prevention practices, and MRSA infection rates.

A total of 54,159 isolation days and 7,628 staff opportunities for donning PPE were observed over a 31-month period. Odds of having an appropriate sign posted were significantly higher after intervention than before intervention (odds ratio [OR], 1.10 [95% confidence interval {CI}, 1.01–1.20]). Relative to baseline, postintervention sign posting improved significantly for airborne and droplet precautions but not for contact precautions. Sign posting improved for vancomycin-resistant enterococci (OR, 1.51 [95% CI, 1.23–1.86]; P = .0001), Clostridium difficile (OR, 1.59 [95% CI, 1.27–2.02]; P = .00005), and Acinetobacter baumannii (OR, 1.41 [95% CI, 1.21–1.64]; P = .00001) precautions but not for MRSA precautions (OR, 1.11 [95% CI, 0.89–1.39]; P = .36). Staff and visitor adherence to PPE remained low throughout the study but improved from 29.1% to 37.0% after the intervention (OR, 1.14 [95% CI, 1.01–1.29]). MRSA infection rates were not significantly different after the intervention.

An electronic surveillance system resulted in small but statistically significant improvements in isolation practices but no reductions in infection rates over the short term. Such innovations likely require considerable uptake time.

To report type and rates of healthcare-associated infections (HAIs) as well as pathogen distribution and antimicrobial resistance patterns from a pilot HAI surveillance system in Egypt.

Prospective surveillance was conducted from April 2011 through March 2012 in 46 intensive care units (ICUs) in Egypt. Definitions were adapted from the Centers for Disease Control and Prevention's National Healthcare Safety Network. Trained healthcare workers identified HAIs and recorded data on clinical symptoms and up to 4 pathogens. A convenience sample of clinical isolates was tested for antimicrobial resistance at a central reference laboratory. Multidrug resistance was defined by international consensus criteria.

ICUs from 11 hospitals collected 90,515 patient-days of surveillance data. Of 472 HAIs identified, 47% were pneumonia, 22% were bloodstream infections, and 15% were urinary tract infections; case fatality among HAI case patients was 43%. The highest rate of device-associated infections was reported for ventilator-associated pneumonia (pooled mean rate, 7.47 cases per 1,000 ventilator-days). The most common pathogens reported were Acinetobacter species (21.8%) and Klebsiella species (18.4%). All Acinetobacter isolates tested (31/31) were multidrug resistant, and 71% (17/24) of Klebsiella pneumoniae isolates were extended-spectrum β-lactamase producers.

Infection control priorities in Egypt should include preventing pneumonia and preventing infections due to antimicrobial-resistant pathogens.

To describe the epidemiology of carbapenem-resistant Enterobacteriaceae (CRE) carriage and acquisition among hospitalized patients in an area of CRE endemicity.

Cohort study with a nested case-control study.

Two acute care, academic hospitals in New York City.

All patients admitted to 7 study units, including intensive care, medical-surgical, and acute rehabilitation units.

Perianal samples were collected from patients at admission and weekly thereafter to detect asymptomatic gastrointestinal carriage of CRE. A nested case-control study was performed to identify factors associated with CRE acquisition. Case patients were those who acquired CRE during a single hospitalization. Control subjects had no microbiologic evidence of CRE and at least 1 negative surveillance sample. Clinical data were abstracted from the medical record.

The prevalence of CRE in the study population was 5.4% (306 of 5,676 patients), and 104 patients met the case definition of acquisition during a single hospital stay. Mechanical ventilation (odds ratio [OR], 11.5), pulmonary disease (OR, 5.2), days of antibiotic therapy (OR, 1.04), and CRE colonization pressure (OR, 1.15) were independently associated with CRE acquisition. Pulsed-field gel electrophoresis analysis identified 87% of tested Klebsiella pneumoniae isolates as sharing related patterns (greater than 78% similarity), which suggests clonal transmission within and between the study hospitals.

Critical illness and underlying medical conditions, CRE colonization pressure, and antimicrobial exposure are important risk factors for CRE acquisition. Adherence to infection control practices and antimicrobial stewardship appear to be critical components of a CRE control program.

To determine whether retractable intravenous devices produced blood splatter and whether blood splatter frequency differed between visual and microscopy detection methods.

In this laboratory-based experiment, 105 venipunctures were performed in a simulated brachial vein containing mock venous blood. The retraction mechanism was activated in a testing chamber with precut fabric filters, placed at 3 different locations, to capture blood splatter. Differences in filter mass, visual inspection, and microscopic analysis for presence of blood on filters were the units of analysis. Descriptive statistics, paired Student t tests, and k statistics were used for data analysis.

Blood splatter was detected visually and microscopically as follows: filter A, 70% and 71%, respectively; filter B, 12% and 9%, respectively; and filter C, 13% and 10%, respectively. A statistically significant difference was observed in the mean mass of filter A between before and after activation when confirmed by the naked eye (P = .014) and microscopically (P = .0092). Substantial agreement between methods was observed for filter A (k = 0.78 [95% confidence interval, 0.64-0.92]), filter B (k = 0.73 [95% confidence interval, 0.51-0.95]), and filter C (k = 0.75 [95% confidence interval, 0.55-0.96]). However, blood was detected by microscopy and not by the naked eye in 7 instances (7%).

Our findings demonstrate that splatter, which can potentially expose healthcare workers (HCWs) to bloodborne pathogens, is associated with the activation of intravascular catheters with retraction mechanisms. HCWs may not detect this splatter when it occurs and may not report a splash to mucous membranes or nonintact skin. The need to wear personal protective equipment when using such devices is reinforced.

Screening for methicillin-resistant Staphylococcus aureus (MRSA) in high-risk patients is a legislative mandate in 9 US states and has been adopted by many hospitals. Definitions of high risk differ among hospitals and state laws. A systematic evaluation of factors associated with colonization is lacking. We performed a systematic review of the literature to assess factors associated with MRSA colonization at hospital admission.

We searched MEDLINE from 1966 to 2012 for articles comparing MRSA colonized and noncolonized patients on hospital or intensive care unit (ICU) admission. Data were extracted using a standardized instrument. Meta-analyses were performed to identify factors associated with MRSA colonization.

We reviewed 4,381 abstracts; 29 articles met inclusion criteria (n = 76,913 patients). MRSA colonization at hospital admission was associated with recent prior hospitalization (odds ratio [OR], 2.4 [95% confidence interval (CI), 1.3–4.7]; P<.01), nursing home exposure (OR, 3.8 [95% CI, 2.3–6.3]; P< .01), and history of exposure to healthcare-associated pathogens (MRSA carriage: OR, 8.0 [95% CI, 4.2–15.1]; Clostridium difficile infection: OR, 3.4 [95% CI, 2.2–5.3]; vancomycin-resistant Enterococci carriage: OR, 3.1 [95% CI, 2.5–4.0]; P< .01 for all). Select comorbidities were associated with MRSA colonization (congestive heart failure, diabetes, pulmonary disease, immunosuppression, and renal failure; P< .01 for all), while others were not (human immunodeficiency virus, cirrhosis, and malignancy). ICU admission was not associated with an increased risk of MRSA colonization (OR, 1.1 [95% CI, 0.6–1.8]; P = .87).

MRSA colonization on hospital admission was associated with healthcare contact, previous healthcare-associated pathogens, and select comorbid conditions. ICU admission was not associated with MRSA colonization, although this is commonly used in state mandates for MRSA screening. Infection prevention programs utilizing targeted MRSA screening may consider our results to define patients likely to have MRSA colonization.

We conducted an investigation after identifying a cluster of 4 serious infections following transrectal ultrasound–guided biopsy of the prostate (TRUBP) during a 2-month period.

veterans Affairs medical center.

Patients with urinary tract infection (UTI) after TRUBP and time-matched controls with no evidence of infection.

The incidence of UTI within 30 days after TRUBP was calculated from 2002 through 2010. We evaluated the correlation between infection with fluoroquinolone-resistant gram-negative bacilli (GNB) and fluoroquinolone resistance in outpatient Escherichia coli urinary isolates and performed a case-control study to determine risk factors for infection with fluoroquinolone-resistant GNB. Processes for TRUBP prophylaxis, procedures, and equipment sterilization were reviewed.

An outbreak of UTI due to fluoroquinolone-resistant E. coli after TRUBP began 2 years before the cluster was identified and was correlated with increasing fluoroquinolone resistance in outpatient E. coli. No deficiencies were identified in equipment processing or biopsy procedures. Fluoroquinolone-resistant E. coli UTI after TRUBP was independently associated with prior infection with fluoroquinolone-resistant GNB (adjusted odds ratio, 20.8; P = .005). A prediction rule including prior UTI, hospitalization in the past year, and previous infection with fluoroquinolone-resistant GNB identified only 17 (49%) of 35 cases.

The outbreak of fluoroquinolone-resistant E. coli infections after TRUBP closely paralleled rising rates of fluoroquinolone resistance among outpatient E. coli isolates. The delayed detection of the outbreak and the absence of sensitive predictors of infection suggest that active surveillance for infection after TRUBP is necessary in the context of increasing fluoroquinolone resistance in the United States.

An analysis of a cluster of New Delhi metallo-β-lactamase-l-producing Klebsiella pneumoniae (NDMl-Kp) and a retrospective case-cohort analysis of risk factors for acquisition in contacts of NDM1-Kp-positive patients.

A 1,100-bed Canadian academic tertiary care center.

Two index patients positive for NDMl-Kp as well as 45 contacts (roommates, ward mates, or environmental contacts) were investigated.

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 NDMl-Kp using chromogenic agar. Presence of blaNDM-1 was confirmed by multiplex polymerase chain reaction. Clonality was assessed with pulsed-field gel electrophoresis (PFGE) using restriction enzyme XbaI.

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 subsequenüy 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); P = .005], trimethoprim-sulfamethoxazole [OR, 11.3 (95% CI, 1.84-70.0); P = .01], and carbapenems [OR, 16.8 (95% CI, 1.79-157.3); P = .04]) and duration of exposure to NDM1-Kp-positive roommates (26.5 vs 6.7 days; P< .001).

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 NDMl-Kp-positive patients require further study.

The year 2010 is the first time that the Rhode Island hospital discharge database included present on admission (POA) indicators, which give us the opportunity to distinguish cases of hospital-onset Clostridium difficile infection (CDI) from cases of community-onset CDI and to assess the burden of hospital-onset CDI in patients discharged from Rhode Island hospitals during 2010 and 2011.

Observational study.

Patients 18 years of age or older discharged from one of Rhode Island's 11 acute-care hospitals between January 1, 2010, and December 31, 2011.

Using the newly available POA indicators in the Rhode Island 2010 and 2011 hospital discharge database, we identified patients with hospital-onset CDI and without CDI. Adjusting for patient demographic and clinical characteristics using propensity score matching, we measured between-group differences in mortality, length of stay, and cost for patients with hospital-onset CDI and without CDI.

In 2010 and 2011, the 11 acute-care hospitals in Rhode Island had 225,999 discharges. Of 4,531 discharged patients with CDI (2.0% of all discharges), 1,211 (26.7%) had hospital-onset CDI. After adjusting for patient demographic and clinical characteristics, discharged patients with hospital-onset CDI were found to have higher mortality rates, longer lengths of stay, and higher costs than those without CDI.

Our results highlight the burden of hospital-onset CDI in Rhode Island. These findings emphasize the need to track longitudinal trends to tailor and target population-health and quality-improvement initiatives.

To determine the attributable in-hospital mortality, length of stay (LOS), and cost of hospital-onset Clostridium difficile infection (HO-CDI).

Propensity score matching.

Six Pennsylvania hospitals (2 academic centers, 1 community teaching facility, and 3 community nonteaching facilities) contributing data to a clinical research database.

Adult inpatients between 2007 and 2008.

We defined HO-CDI in adult inpatients as a positive C. difficile toxin assay result from a specimen collected more than 48 hours after admission and more than 8 weeks following any previous positive result. We developed an HO-CDI propensity model and matched cases with noncases by propensity score at a 1 : 3 ratio. We further restricted matching within the same hospital, within the same principal disease group, and within a similar length of lead time from admission to onset of HO-CDI.

Among 77,257 discharges, 282 HO-CDI cases were identified. The propensity score-matched rate was 90%. Compared with matched noncases, HO-CDI patients had higher mortality (11.8% vs 7.3%; P<.05), longer LOS (median [interquartile range (IQR)], 12 [9–21] vs 11 [8–17] days; P< .01), and higher cost (median [IQR], $20,804 [$ll,059-$38,429] vs $16,634 [$9,413–$30,319]; P< .01). The attributable effect of HO-CDI was 4.5% (95% confidence interval [CI], 0.2%–8.7%; P<.05) for mortality, 2.3 days (95% CI, 0.9–3.8; P<.01) for LOS, and $6,117 (95% CI, $1,659–$10,574; P<.01) for cost.

Patients with HO-CDI incur additional attributable mortality, LOS, and cost burden compared with patients with similar primary clinical condition, exposure risk, lead time of hospitalization, and baseline characteristics.