Risk Factors and Outcomes for Bloodstream Infections (BSI) Among Patients with Acute Bacterial Skin and Skin Structure Infections (ABSSSI)

Abstract

Background ABSSSI are common infections in the community and can result in high morbidity and healthcare costs. While risk factors for ABSSSI have been previously evaluated, risk factors associated with secondary BSI have not, especially in an urban population with limited access to healthcare.Methods This case–control study evaluated risk factors and outcomes associated with secondary S. aureus BSI among adult ABSSSI patients. Patients age ≥ 18 years with an ABSSSI diagnosis presenting to two academic medical centers in Detroit, MI from 2010 to 2015 were included. Baseline/clinical characteristics and outcomes were compared between cases (ABSSSI + BSI) and controls (ABSSSI). Outcomes included in-hospital mortality, hospital length of stay (los) and 30-day reinfection. Fisher’s exact and Student’s t- or Mann–Whitney U-tests were used for bivariate comparisons. Variables associated with ABSSSI + BSI in bivariate analysis at a P-value < 0.1 were included in multivariable logistic regression to examine factors independently associated with ABSSSI + BSI.Results392 patients consisting of 196 ABSSSI + BSI and 196 controls ABSSSI were evaluated. In bivariate analysis, individuals with ABSSSI + BSI were significantly older (P < 0.001), more likely to be male (P = 0.008), be an intravenous drug user (P = 0.012), have chronic renal failure (P = 0.002), prior hospitalization (P <0.001), and more systemic symptoms, such as elevated temperature, white blood cell count, and acute renal failure on hospital admission (P < 0.001). By regression, male gender (aOR 1.85, 95% CI 11–3.66), acute renal failure (aOR 2.08, 95% CI 1.18–3.67), intravenous drug use (aOR 4.38, 95% CI 2.22–8.62), and prior hospitalization (aOR 2.41, 95% CI 1.24–4.93) remained statistically significant. ABSSSI + BSI patients were more likely to experience in-hospital mortality (4.1 vs. 0%, P <0.001), have longer mean loss (7.4 ± 5.7 vs. 2.7 ± 2.2 days, P = <0.001), and experience 30-day reinfection (11.2 vs. 4.1%, P = 0.006).Conclusion Patients with ABSSSI + BSI had worse outcomes than those with ABSSSI alone. Factors associated with ABSSSI + BSI, such as gender, IVDU, prior hospitalization, renal failure, and systemic signs/symptoms of infection, may be used to identify patients at risk for ABSSSI + BSI.Disclosures All authors: No reported disclosures.