Isaac See

NAP1 Strain Type Predicts Outcomes from Clostridium difficile Infection

BACKGROUND Studies are conflicting regarding the importance of the fluoroquinolone-resistant North American pulsed-field gel electrophoresis type 1 (NAP1) strain in Clostridium difficile infection (CDI) outcome. We describe strain types causing CDI and evaluate their association with patient outcomes. METHODS CDI cases were identified from population-based surveillance. Multivariate regression models were used to evaluate the associations of strain type with severe disease (ileus, toxic megacolon, or pseudomembranous colitis within 5 days; or white blood cell count ≥15 000 cells/µL within 1 day of positive test), severe outcome (intensive care unit admission after positive test, colectomy for C. difficile infection, or death within 30 days of positive test), and death within 14 days of positive test. RESULTS Strain typing results were available for 2057 cases. Severe disease occurred in 363 (17.7%) cases, severe outcome in 100 (4.9%), and death within 14 days in 56 (2.7%). The most common strain types were NAP1 (28.4%), NAP4 (10.2%), and NAP11 (9.1%). In unadjusted analysis, NAP1 was associated with greater odds of severe disease than other strains. After controlling for patient risk factors, healthcare exposure, and antibiotic use, NAP1 was associated with severe disease (adjusted odds ratio [AOR], 1.74; 95% confidence interval [CI], 1.36-2.22), severe outcome (AOR, 1.66; 95% CI, 1.09-2.54), and death within 14 days (AOR, 2.12; 95% CI, 1.22-3.68). CONCLUSIONS NAP1 was the most prevalent strain and a predictor of severe disease, severe outcome, and death. Strategies to reduce NAP1 prevalence, such as antibiotic stewardship to reduce fluoroquinolone use, might reduce CDI morbidity.

Emergency Department Visits and Hospitalizations for Digoxin Toxicity: United States, 2005-2010

Background— Recent data on digoxin prescribing and adverse events are lacking but could help inform the management of digoxin in contemporary heart failure treatment. Methods and Results— We determined nationally representative numbers and rates of emergency department (ED) visits for digoxin toxicity in the United States using 2005 to 2010 reports from the National Electronic Injury Surveillance System–Cooperative Adverse Drug Event Surveillance project and the National Ambulatory (and Hospital Ambulatory) Medical Care Surveys. Based on 441 cases, an estimated 5156 (95% confidence interval [CI], 2663–7648) ED visits for digoxin toxicity occurred annually in the United States; more than three fourths (78.8% [95% CI, 73.5%–84.1%]) resulted in hospitalization. Serum digoxin level was ≥2.0 ng/mL for 95.8% (95% CI, 93.2%–98.4%) of estimated ED visits with levels reported (n=251 cases). The rate of ED visits per 10 000 outpatient prescription visits among patients ≥85 years was twice that of patients 40 to 84 years (rate ratio, 2.4 [95% CI, 1.2–5.0]); among women, the rate was twice that of men (rate ratio, 2.3 [95% CI, 1.1–4.7]). Digoxin toxicity accounted for an estimated 1.0% (95% CI, 0.6%–1.4%) of ED visits for all adverse drug events among patients ≥40 years, but an estimated 3.3% (95% CI, 2.3%–4.4%) of ED visits and 5.9% (95% CI, 4.0%–7.9%) of hospitalizations for all adverse drug events among patients ≥85 years. Estimated annual ED visits and hospitalizations remained relatively constant from 2005 to 2010. Conclusions— Digoxin toxicity is not declining; more careful prescribing to high-risk groups and improved monitoring of serum levels might be needed to reduce morbidity from outpatient digoxin use.

Causative Organisms and Associated Antimicrobial Resistance in Healthcare-Associated, Central Line–Associated Bloodstream Infections From Oncology Settings, 2009–2012

BACKGROUND Recent antimicrobial resistance data are lacking from inpatient oncology settings to guide infection prophylaxis and treatment recommendations. We describe central line-associated bloodstream infection (CLABSI) pathogens and antimicrobial resistance patterns reported from oncology locations to the Centers for Disease Control and Preventions National Healthcare Safety Network (NHSN). METHODS CLABSI data reported to NHSN from 2009 to 2012 from adult inpatient oncology locations were compared to data from nononcology adult locations within the same hospitals. Pathogen profile, antimicrobial resistance rates, and CLABSI incidence rates per 1000 central line-days were calculated. CLABSI incidence rates were compared using Poisson regression. RESULTS During 2009-2012, 4654 CLABSIs were reported to NHSN from 299 adult oncology units. The most common organisms causing CLABSI in oncology locations were coagulase-negative staphylococci (16.9%), Escherichia coli (11.8%), and Enterococcus faecium (11.4%). Fluoroquinolone resistance was more common among E. coli CLABSI in oncology than nononcology locations (56.5% vs 41.5% of isolates tested; P < .0001) and increased significantly from 2009-2010 to 2011-2012 (49.5% vs 60.4%; P = .01). Furthermore, rates of CLABSI were significantly higher in oncology compared to nononcology locations for fluoroquinolone-resistant E. coli (rate ratio, 7.37; 95% confidence interval [CI], 6.20-8.76) and vancomycin-resistant E. faecium (rate ratio, 2.27, 95% CI, 2.03-2.53). However, resistance rates for some organisms, such as Klebsiella species and Pseudomonas aeruginosa, were lower in oncology than in nononcology locations. CONCLUSIONS Antimicrobial-resistant E. coli and E. faecium have become significant pathogens in oncology. Practices for antimicrobial prophylaxis and empiric antimicrobial therapy should be regularly assessed in conjunction with contemporary antimicrobial resistance data.

Mucosal Barrier Injury Laboratory-Confirmed Bloodstream Infections (MBI-LCBI): Descriptive Analysis of Data Reported to National Healthcare Safety Network (NHSN), 2013

OBJECTIVES To determine the impact of mucosal barrier injury laboratory-confirmed bloodstream infections (MBI-LCBIs) on central-line-associated bloodstream infection (CLABSI) rates during the first year of MBI-LCBI reporting to the National Healthcare Safety Network (NHSN) DESIGN Descriptive analysis of 2013 NHSN data SETTING Selected inpatient locations in acute care hospitals METHODS A descriptive analysis of MBI-LCBI cases was performed. CLABSI rates per 1,000 central-line days were calculated with and without the inclusion of MBI-LCBIs in the subset of locations reporting ≥1 MBI-LCBI, and in all locations (regardless of MBI-LCBI reporting) to determine rate differences overall and by location type. RESULTS From 418 locations in 252 acute care hospitals reporting ≥1 MBI-LCBIs, 3,162 CLABSIs were reported; 1,415 (44.7%) met the MBI-LCBI definition. Among these locations, removing MBI-LCBI from the CLABSI rate determination produced the greatest CLABSI rate decreases in oncology (49%) and ward locations (45%). Among all locations reporting CLABSI data, including those reporting no MBI-LCBIs, removing MBI-LCBI reduced rates by 8%. Here, the greatest decrease was in oncology locations (38% decrease); decreases in other locations ranged from 1.2% to 4.2%. CONCLUSIONS An understanding of the potential impact of removing MBI-LCBIs from CLABSI data is needed to accurately interpret CLABSI trends over time and to inform changes to state and federal reporting programs. Whereas the MBI-LCBI definition may have a large impact on CLABSI rates in locations where patients with certain clinical conditions are cared for, the impact of MBI-LCBIs on overall CLABSI rates across inpatient locations appears to be more modest. Infect. Control Hosp. Epidemiol. 2015;37(1):2-7.

Socioeconomic Factors Explain Racial Disparities in Invasive Community-Associated Methicillin-Resistant Staphylococcus aureus Disease Rates

Background Invasive community-associated methicillin-resistant Staphylococcus aureus (MRSA) incidence in the United States is higher among black persons than white persons. We explored the extent to which socioeconomic factors might explain this racial disparity. Methods A retrospective cohort was based on the Centers for Disease Control and Preventions Emerging Infections Program surveillance data for invasive community-associated MRSA cases (isolated from a normally sterile site of an outpatient or on hospital admission day ≤3 in a patient without specified major healthcare exposures) from 2009 to 2011 in 33 counties of 9 states. We used generalized estimating equations to determine census tract-level factors associated with differences in MRSA incidence and inverse odds ratio-weighted mediation analysis to determine the proportion of racial disparity mediated by socioeconomic factors. Results Annual invasive community-associated MRSA incidence was 4.59 per 100000 among whites and 7.60 per 100000 among blacks (rate ratio [RR], 1.66; 95% confidence interval [CI], 1.52-1.80). In the mediation analysis, after accounting for census tract-level measures of federally designated medically underserved areas, education, income, housing value, and rural status, 91% of the original racial disparity was explained; no significant association of black race with community-associated MRSA remained (RR, 1.05; 95% CI, .92-1.20). Conclusions The racial disparity in invasive community-associated MRSA rates was largely explained by socioeconomic factors. The specific factors that underlie the association between census tract-level socioeconomic measures and MRSA incidence, which may include modifiable social (eg, poverty, crowding) and biological factors (not explored in this analysis), should be elucidated to define strategies for reducing racial disparities in community-associated MRSA rates.

Emerging Infections Program as Surveillance for Antimicrobial Drug Resistance.

This program is a national resource for data on the epidemiology of antimicrobial drug–resistant infections and characteristics of isolates.

Outbreak of Tsukamurella spp. Bloodstream Infections among Patients of an Oncology Clinic—West Virginia, 2011–2012

OBJECTIVE To determine the source and identify control measures of an outbreak of Tsukamurella species bloodstream infections at an outpatient oncology facility. DESIGN Epidemiologic investigation of the outbreak with a case-control study. METHODS A case was an infection in which Tsukamurella species was isolated from a blood or catheter tip culture during the period January 2011 through June 2012 from a patient of the oncology clinic. Laboratory records of area hospitals and patient charts were reviewed. A case-control study was conducted among clinic patients to identify risk factors for Tsukamurella species bloodstream infection. Clinic staff were interviewed, and infection control practices were assessed. RESULTS Fifteen cases of Tsukamurella (Tsukamurella pulmonis or Tsukamurella tyrosinosolvens) bloodstream infection were identified, all in patients with underlying malignancy and indwelling central lines. The median age of case patients was 68 years; 47% were male. The only significant risk factor for infection was receipt of saline flush from the clinic during the period September-October 2011 (P = .03), when the clinic had been preparing saline flush from a common-source bag of saline. Other infection control deficiencies that were identified at the clinic included suboptimal procedures for central line access and preparation of chemotherapy. CONCLUSION Although multiple infection control lapses were identified, the outbreak was likely caused by improper preparation of saline flush syringes by the clinic. The outbreak demonstrates that bloodstream infections among oncology patients can result from improper infection control practices and highlights the critical need for increased attention to and oversight of infection control in outpatient oncology settings.

Incidence and Pathogen Distribution of Healthcare-Associated Infections in Pilot Hospitals in Egypt

OBJECTIVE 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. METHODS 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 Preventions 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. RESULTS 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. CONCLUSIONS Infection control priorities in Egypt should include preventing pneumonia and preventing infections due to antimicrobial-resistant pathogens.

Pathogen distribution and antimicrobial resistance among pediatric healthcare-associated infections reported to the National Healthcare Safety Network, 2011-2014

OBJECTIVE To describe pathogen distribution and antimicrobial resistance patterns for healthcare-associated infections (HAIs) reported to the National Healthcare Safety Network (NHSN) from pediatric locations during 2011-2014. METHODS Device-associated infection data were analyzed for central line-associated bloodstream infection (CLABSI), catheter-associated urinary tract infections (CAUTI), ventilator-associated pneumonia (VAP), and surgical site infection (SSI). Pooled mean percentage resistance was calculated for a variety of pathogen-antimicrobial resistance pattern combinations and was stratified by location for device-associated infections (neonatal intensive care units [NICUs], pediatric intensive care units [PICUs], pediatric oncology and pediatric wards) and by surgery type for SSIs. RESULTS From 2011 to 2014, 1,003 hospitals reported 20,390 pediatric HAIs and 22,323 associated pathogens to the NHSN. Among all HAIs, the following pathogens accounted for more than 60% of those reported: Staphylococcus aureus (17%), coagulase-negative staphylococci (17%), Escherichia coli (11%), Klebsiella pneumoniae and/or oxytoca (9%), and Enterococcus faecalis (8%). Among device-associated infections, resistance was generally lower in NICUs than in other locations. For several pathogens, resistance was greater in pediatric wards than in PICUs. The proportion of organisms resistant to carbapenems was low overall but reached approximately 20% for Pseudomonas aeruginosa from CLABSIs and CAUTIs in some locations. Among SSIs, antimicrobial resistance patterns were similar across surgical procedure types for most pathogens. CONCLUSION This report is the first pediatric-specific description of antimicrobial resistance data reported to the NHSN. Reporting of pediatric-specific HAIs and antimicrobial resistance data will help identify priority targets for infection control and antimicrobial stewardship activities in facilities that provide care for children. Infect Control Hosp Epidemiol 2018;39:1-11.

Impact of removing mucosal barrier injury laboratory-confirmed bloodstream infections from central line–associated bloodstream infection rates in the National Healthcare Safety Network, 2014

&NA; Central line–associated bloodstream infection (CLABSI) event data reported to the National Healthcare Safety Network from 2014, the first year of required use of the mucosal barrier injury laboratory‐confirmed bloodstream infection (MBI‐LCBI) definition, were analyzed to assess the impact of removing MBI‐LCBI events from CLABSI rates. CLABSI rates decreased significantly in some location types after removing MBI‐LCBI events, and MBI‐LCBI events will be removed from publicly reported CLABSI rates.