2416. Risk Factors and Outcomes of Bacteremia Caused by Carbapenem-Resistant Enterobacteriaceae Compared With Carbapenem Susceptible Enterobacteriaceae

Abstract

BackgroundDue to shrinking therapeutic options, infections due to Carbapenem-resistant enterobacteriaceae (CRE) are an urgent threat in healthcare systems across the world. While the CRE phenotype is determined by a number a different genes, the metallo β-lactamases such as the NDM, are particularly prevalent in the South Asian region. Data regarding infections with CRE caused by these strains is relatively limited. Our objective was to compare the risk factors and outcomes (mortality and length of hospitalization) of bacteremia secondary to CRE with bacteremia secondary to carbapenem susceptible enterobacteriaceae (CSE).MethodsWe conducted a cross-sectional study on patients admitted between 2013 and 2016, to a large tertiary care hospital in Karachi, Pakistan. Patients with CRE bacteremia were matched for the same year with patients with bacteremia due to CSE. Patients with polymicrobial blood cultures were excluded. Clinical data of these patients were obtained using a structured performa.ResultsA total of 131 patients were enrolled (65 CRE and 66 CSE). The mean age was similar in both groups (51.8 years and 57.1 years in CRE and CSE patients respectively). Compared with CSE, CRE bacteremia was more likely to occur in patients with Diabetes Mellitus or those with a tracheostomy (P = 0.002 and 0.014, respectively). The most common source of CRE bacteremia was central line associated (24.6% of all cases) as opposed to urinary tract infections in those with CSE bacteremia (62.1% of all cases). Fewer patients with CRE bacteremia received appropriate antibiotics (72.3% vs. 81.8%). Mortality was over three times higher in patients with CRE (41.5% vs. 12.1%, P = 0.001). The mortality remained higher when adjusted for the severity of illness using the PITT-bacteremia score. Increased mortality was also associated with central venous catheterization in both CRE and CSE bacteremia, while urinary catheterization and hemodialysis were associated with mortality in patients in CSE bacteremia only. While length of ICU stay was similar between the two groups, the median length of hospital stay was longer in patients with CRE (median of 8 days vs. 6 days, P = 0.021)ConclusionCRE bacteremia was more likely associated with central lines and led to significantly higher mortality and length of stay.Disclosures All authors: No reported disclosures.