Organism-specific bacteremia by hemodialysis access.

BACKGROUND: Data on hemodialysis (HD)-related organism specific bacteremia rates by type of access over an extended period are scant in the literature. Using a registry data base we examined all positive blood cultures by organisms for each type of HD access over 14 years. METHODS: The IRB-approved registry data collection of prevalent patients at our HD unit from 1/1/1999 through 12/31/2012 was analyzed. All positive blood cultures were recorded and expressed as episodes/1,000 days by access type: arteriovenous fistula (AVF), arteriovenous graft (AVG), and central venous catheter (CVC). RESULTS: The rate of positive blood cultures in patients with CVCs was 1.86/1,000 days and was much higher than in patients with an AVF (0.08/1,000 days, p < 0.001) or an AVG (0.31/1,000 days, p < 0.002). There was considerable fluctuation in the bacteremia rate in CVCs with a spike during 2004 - 2008, due predominately to coagulase-negative staphylococcus (CNS) bacteremia. The rate subsequently decreased after retraining of staff. The exit site infection (ESI) rate of CVCs was low, suggesting this was not contributing to the cause of the increase rate of CNS bacteremia. Those patients using a CVC had a markedly increased risk of multiple episodes compared to those using an AVF. Bacteremia with Pseudomonas, polymicrobial, and fungal organisms occurred only in those with a CVC. CONCLUSIONS: The frequency and type of positive blood culture in HD patients are highly associated with type of access used. The high rate of CNS bacteremia with CVC in conjunction with low ESI rate suggests that contamination at the time of accessing the catheter may be the problem. Staff training was followed by a decrease in infection rates. Trending organism-specific bacteremia infection rates in HD units may provide important clues to bacteremia causality and thus prevention.

Clostridium difficile infections in outpatient dialysis cohort.

We examined the Clostridium difficile infection rate and risk factors in an outpatient dialysis cohort. The Cox proportional hazard for developing C. difficile infection was significantly higher with high comorbidity index and low serum albumin level. Conversely, it was lower for patients who had frequent bloodstream and dialysis access-related infections.

Comparison of infectious complications between incident hemodialysis and peritoneal dialysis patients.

The impact of dialysis modality on infection, especially early in the course of dialysis, has not been well studied. This study compared infection between hemodialysis (HD) and peritoneal dialysis (PD) from the start of dialysis and evaluated factors that have an impact on infection risk. In this observational cohort study, all incident dialysis patients (n = 181; HD 119 and PD 62) at a single center from 1999 to 2005 had data collected prospectively beginning day 1 of dialysis. Excluded were those with any previous ESRD therapy. Infection rates were evaluated using multivariate Poisson regression. Overall infection rates were similar (HD 0.77 versus PD 0.86/yr; P = 0.24). Only HD patients had bacteremia (0.16/yr), and only PD patients had peritonitis (0.24/yr). Bacteremia that occurred < or =90 d after start of HD was 0.44/yr, increased compared with overall rate of 0.16/yr (P < 0.004). HD catheters, used in 67% of patients who started HD, were associated with a strikingly increased rate of bacteremia. Peritonitis < or =90 d was 0.22/yr, no different from the overall rate. Modality was not an independent predictor of overall infections (PD versus HD: relative risk 1.30; 95% confidence interval 0.93 to 1.8; P = 0.12) using multivariate analysis. PD and HD patients had similar infection rates overall, but type of infection and risk over time varied. HD patients had an especially high risk for bacteremia in the first 90 d, whereas the risk for peritonitis for the PD cohort was not different over time. These results support the placement of permanent accesses (fistula or PD catheter) before the start of dialysis to avoid use of HD catheters.