Background: More than 450,000 patients receive outpatient hemodialysis in the United States. Patients on hemodialysis are at high risk of bloodstream infections (BSIs), which are associated with significant morbidity and mortality. National prevention efforts targeting hemodialysis facilities have resulted in widespread changes in practice, including modifications to central venous catheter (CVC) maintenance procedures. We analyzed dialysis event surveillance data submitted to the CDC NHSN to describe changes in BSI rates among hemodialysis outpatients from 2014 to 2018. Methods: Outpatient hemodialysis facilities report BSIs (ie, positive blood cultures collected in the outpatient setting or within 1 calendar day after hospital admission) and the number of hemodialysis outpatients treated during the first 2 working days of each month to the NHSN. For each BSI, the suspected source (ie, vascular access, another site, contamination, or uncertain) and vascular access type are indicated: CVC, arteriovenous fistula (AVF) or arteriovenous graft (AVG). Pooled mean rates (per 100 patient months) were calculated for BSIs, access-related BSIs (ARBSIs), and BSIs and ARBSIs were stratified by vascular access type. Annual BSI rate trends were evaluated using a negative binomial regression model, which treated patient months as an offset variable and included access type, year, and an access-year interaction variable. Results: More than 6,000 outpatient hemodialysis facilities reported 134,961 BSIs from 2014 to 2018. Of these BSIs, 102,505 (76%) were categorized as access related. CVCs were present in 63% of BSIs and 70% of ARBSIs. Pooled mean BSI rates decreased 27% from 0.64 to 0.47 per 100 patient months; rates of ARBSIs decreased 27% from 0.49 to 0.36 per 100 patient months. Significant decreases in event rates occurred across vascular access strata (Fig. 1). The reduction in BSI and ARBSI burden was most pronounced among patients with CVCs. BSI rates in patients with CVCs decreased 32% from 2.16 per 100 patient months to 1.46 (annual average decrease, 9.5%), and ARBSI rates in patients with CVCs decreased 32% from 1.83 per 100 patient months to 1.24 (annual average decrease, 9.4%). Conclusions: Substantial reductions in BSI and ARBSI rates among hemodialysis outpatients occurred during this 5-year period, and these reductions appear to be most prominent among CVC and AVF patients. Improvements in infection prevention and control practices, including CVC care, have likely contributed to these reductions. Additional efforts to increase the uptake of known prevention practices and to identify new strategies for prevention might contribute to continued decreases in infections among this highly vulnerable population.

Funding: None

Disclosures: None

We implemented 2 interventions to improve utilization and contamination at our institution: kits to improve appropriate sample collection and an electronic order alert displaying appropriate indications of fungal blood cultures. An electronic order alert when ordering fungal blood cultures was associated with decreased utilization without decrease in positivity rate.

Background: The prevalence of healthcare-acquired infections (HAIs) and rising levels of antimicrobial resistance place a significant burden on modern healthcare systems. Cultures are typically used to track HAIs; however, culture methods provide limited information and are not applicable to all pathogens. Next-generation sequencing (NGS) can detect and characterize pathogens present within a sample, but few research studies have explored how NGS could be used to detect pathogen transmission events under HAI-relevant scenarios. The objective of this CDC-funded project was to evaluate and correlate sequencing approaches for pathogen transmission with standard culture-based analysis. Methods: We modeled pathogen transfer via hand contact using synthetic skin. These skin coupons were seeded with a community of commensal organisms to mimic the human skin microbiome. Pathogens were added at physiologically relevant high or low levels prior to skin-to-skin contact. The ESKAPE pathogens: E. faecium, S. aureus, K. pneumoniae, A. baumannii, P. aeruginosa, and Enterobacter spp plus C. difficile were employed because they are the most common antibiotic resistant HAIs. Pathogen transfer between skin coupons was measured following direct skin contact and fomite surface transmission. The effects of handwashing or fomite decontamination were also evaluated. Transferred pathogens were enumerated via culture to establish a robust data set against which DNA and RNA sequence analyses of the same samples could be compared. These data also provide a quantitative assessment of individual ESKAPE+C pathogen transfer rates in skin contact scenarios. Results: Metagenomic and metatranscriptomic analysis using custom analysis pipelines and reference databases successfully identified the commensal and pathogenic organisms present in each sample at the species level. This analysis also identified antibiotic resistance genes and plasmids. Metatranscriptomic analysis permitted not only gene identification but also confirmation of gene expression, a critical factor in the evaluation of antibiotic resistance. DNA analysis does not require cell viability, a key differentiator between sequencing and culturing reflected in simulated handwashing data. Sensitivity remains a key limitation of metagenomic analysis, as shown by the poor species identification and gene content characterization of pathogens present at low abundance within the simulated microbial community. Species level identification typically failed as ratios fell below 1:1,000 pathogen CFU:total community CFU. Conclusions: These findings demonstrate the strengths and weaknesses of NGS for molecular epidemiology. The data sets produced for this study are publicly available so they can be employed for future metagenomic benchmarking studies.

Funding: None

Disclosures: None