757Comparison of Nephrotoxicity in Outpatient Parenteral Antimicrobial Therapy (OPAT) Patients Receiving Beta-lactams or Vancomycin

Background. Outpatient parenteral antimicrobial therapy (OPAT) programs are growing as a cost-effective, safe, and practical way to treat patients with complicated infections outside of the hospital. The guidelines for therapeutic monitoring of vancomycin state that there is minimal difference in incidence of toxicity between vancomycin and beta-lactams. However, there are few studies describing the use of vancomycin in the OPAT setting. Methods. Retrospective chart review was conducted of patients enrolled in the OPAT program who received vancomycin or a beta-lactam for an orthopedic or neurosurgical indication between 2008 and 2010. Inclusion criteria included patients 18 years or older with an intended treatment duration of at least two weeks. Exclusion criteria were patients who received both vancomycin and a beta-lactam. Results. 267 patients were included. The median age was 53.7 (range 20.1-87.5) years in the beta-lactam group (n = 146) and 57.7 (range 20.4-86.8) years in the vancomycin group (n = 121). The anticipated duration of therapy was roughly equivalent (37 vs 38 days), as was the length of stay prior to discharge (7 vs 6 days). There was no significant difference in OPAT treatment setting, site of infection or comorbidities between the vancomycin and beta-lactam groups. Nephrotoxicity occurred more frequently in the vancomycin group than the beta-lactam group (13% vs 3%, p = 0.001). Patients with a body mass index (BMI) > 30 did not experience higher rates of vancomycin induced nephrotoxicity than those with a BMI < 30. In patients who experienced OPAT nephrotoxicity on vancomycin, there was no difference in the number of patients with prior kidney injury vs those without a history of kidney injury. Conclusion. Rates of nephrotoxity were significantly higher in patients receiving vancomycin compared to patients receiving beta-lactams in the outpatient setting. The study was limited by sample size but further research should include identifying inpatient risk factors that correlate to development of nephrotoxicity in OPAT. Disclosures. All authors: No reported disclosures.