Hospitalizations with Healthcare-associated Complicated Skin and Skin Structure Infections: Inappropriate Empiric Therapy and Outcomes

Background: Healthcare-associated infection (HCAI) identifies patients presenting from the community with potentially resistant bacterial pathogens. Importance of appropriate empiric therapy (AET) in HCAI has been established in some infection types. Little work has focused on HCA complicated skin and skin structure infections (cSSSI). Objective: We conducted a retrospective cohort study 4/06-12/07 to explore the impact of non-AET on outcomes among patients hospitalized with HCA-cSSSI. Methods: We defined HCA-cSSSI as presentation with >1 risk factors; 1) recent hospitalization; 2) recent antibiotics; 3) hemodialysis; 4) nursing home residence. We defined AET as receiving antimicrobials active against the pathogen(s) within 24 hours of obtaining culture specimen and computed the impact of inappropriate AET on hospital length of stay (LOS) and mortality. Results: Of the 717 patients with culture-positive cSSSI, 527 (73.5%) were HCAI, of whom 405 (76.9%) received AET. A higher proportion of those receiving non-AET than AET had a decubitus ulcer (29.5% vs. 10.9%, p <0.001), a device-associated infection (42.6% vs. 28.6%, p=0.004), or bacteremia (68.9% vs. 57.8%, p=0.028). MRSA prevalence did not differ between groups. Unadjusted mortality rate was low and did not vary based on initial treatment. Crude hospital LOS was >3 days longer in those treated with non-AET. In a multivariable analysis adjusting for potential confounders, non-AET had an attributable increase in hospital LOS of 1.8 days (95% CI 1.4-2.3). Conclusions: Similar to other populations with HCAI, HCA-cSSSI patients are likely to receive inappropriate empiric therapy for their infection. This early exposure is associated with a significant prolongation of the hospitalization by nearly 2 days. [Study funded by Ortho-McNeil Janssen Scientific Affairs, LLC, Raritan, NJ]