Secular trends of bloodstream infections in hemodialysis patients: insights from a longitudinal Swiss study.

Background: Hemodialysis-associated bloodstream infections (BSIs) represent a significant burden for patients. Understanding the trends in BSIs among hemodialysis patients is crucial for informing strategies to reduce their incidence and improve patient outcomes. This study aimed to evaluate secular trends, identify causative organisms, assess resistance patterns, and determine the sources of hemodialysis-associated BSIs at Geneva University Hospitals, where Staphylococcus aureus screening and decolonization of hemodialysis patients have been implemented since the year 2000.

Methods: A longitudinal cohort study was conducted using data from 2006 to 23. We included all patients receiving maintenance hemodialysis treatment at our institution. A hemodialysis-associated BSI was defined as BSI occurring during active hemodialysis treatment and diagnosed either during hospital admission or in outpatient hemodialysis unit. Outcomes included incidence rates of hemodialysis-associated BSIs, trends in causative pathogens, sources, and resistant organisms. Poisson regression was used to model trends over time of incidence rate ratios (IRR).

Results: A total of 313 true BSI episodes were identified in 218 hemodialysis patients over 11,413 patient-hemodialysis months. The overall BSI incidence rate was 2.7 episodes per 100 patient-hemodialysis-months, with a consistent decrease over time. Compared to 2006-08, hemodialysis-associated BSI rates decreased by 16% in 2009-11 (IRR 0.84, 95% confidence interval [CI] 0.60-1.18), and by a maximum of 44% in 2021-23 (IRR 0.56, 95% CI 0.36-0.83). The decreasing trend was mainly due to reduced S. aureus BSIs, while Enterobacterales BSIs rates remained stable. Catheter-related BSIs accounted for 41.5% of infections (130/313), with marked reduction following 2014. BSIs caused by resistant bacteria were rare, with decreasing trends of methicillin-resistant S. aureus.

Conclusions: Hemodialysis-associated BSI rates significantly declined, driven largely by reductions in S. aureus BSIs and catheter-related infections. No replacement by Gram-negative BSI was observed. Prevention of hemodialysis-associated BSI is key for reducing infection burden among hemodialysis patients.