857A Case Control Study of the Risk Factors for Central Venous Catheter Related Mixed Candidemia Infection

Background. Central venous catheters (CVC) are a major risk factor for candidemia. Mixed candidemia with bacteremia due to CVCs has been increasingly reported in recent times. However, the risk factors for this dual infection have not been clearly identified. The aim of this study was to identify the risk factors for CVC associated mixed candidemia. Methods. This was a prospective case control study conducted at a tertiary care hospital in South India which included all the patients with CVC related candidemia from May 2011 to July 2013. Inpatients with CVC insitu for >48 hours with candida isolated from blood were considered as CVC related candidemia. Mixed infection was defined as the isolation of both Candida and bacteria from a single set or different sets of blood cultures obtained within a 48 hours period. Cases (mixed infection) were compared with controls (only candidemia) with respect to risk factors and outcome. The chi-square test test were used to compare categorical variables, and Student’s t-test was used to compare continuous variables. Statistical analysis was performed using SPSS version 16.0. Results. During the study period, there were a total of 103 episodes of candidemia of which 33 (32%) episodes were due to mixed candidemia. Most of the mixed infections were due to gram negative bacteria (67%). In multivariate analysis, risk factors associated with CVC related mixed candidemia were prior ICU stay > 4 weeks (odds ratio; 95% Confidence Interval (CI): 3.39; 1.4, 7.2), prior antibiotic use > 14 days (2.73; 1.3, 5.9), > 3 antibiotics (6.55; 3, 14.3) and blood transfusions (4.02; 2.2, 7.4). There was no difference in the duration or site of CVC or the distribution of Candida species in the two groups. The 30-day survival of cases was significantly lower than controls (12.1% vs 42.9%; p = 0.002). Conclusion. Mixed candidemia is relatively frequent with CVC related candidemia and negatively impacts the outcome. Duration of ICU stay, number and duration of antibiotic usage are risk factors associated with not only CVC associated candidemia but also for mixed infection. However, our study found blood transfusion as an additional risk factor for mixed candidemia. Further studies on the clinical relevance of Candida bacterial interactions are needed. Disclosures. All authors: No reported disclosures.