1116. Comparison of Short-Course vs. Prolonged-Course Antimicrobial Therapy in the Management of Intra-Abdominal Infections

BACKGROUND: When managing complicated intra-abdominal infections (IAIs), the current Infectious Diseases Society of America (IDSA) guidelines recommend an antimicrobial treatment duration of 4–7 days. Although recent evidence supports this shorter course of therapy, antimicrobials are still often administered for 10–14 days due to concern for subsequent complications. The purpose of this study was to compare clinical outcomes of short-course (SC) vs. prolonged-course (PC) antimicrobial therapy in the management of IAI at our institution. METHODS: IRB-approved, single-center, retrospective cohort including all patients at the University of Toledo Medical Center who were admitted between January 1, 2012–June 30, 2017 with an IAI, received antimicrobials for ≥48 hours, and had at least one sign of IAI. Patients with concomitant infections at sites other than the abdomen, primary peritonitis or pancreatitis, immunocompromising conditions, or bacteremia were excluded. Primary outcome of clinical cure was compared between SC (≤7 days of antimicrobial treatment) and PC (>7 days) groups. Secondary outcomes included hospital length of stay (LOS), ICU LOS, 28-day all-cause mortality, and 30-day readmission. Multivariable logistic regression was performed to assess for factors associated with clinical cure. RESULTS: One hundred seventy-five patients were included, 73 SC and 102 PC. Baseline characteristics were similar between groups. Rate of clinical cure for SC vs. PC was 74.0% vs. 67.6% (P = 0.367). Secondary outcomes including hospital LOS (5.5 days vs. 5.8 days, P = 0.372), ICU LOS (3.0 days vs. 5.0 days, P = 0.117), 28-day all-cause mortality (4.1% vs. 2.0%, P = 0.651), and 30-day readmission (19.2% vs. 20.6%, P = 0.818) were also not significantly different. After multivariable logistic regression, the only variable independently associated with clinical cure was diverticulitis (adjusted odds ratio 0.337, 95% CI 0.133 – 0.853). CONCLUSION: In patients with IAI, there was no significant difference observed in rates of clinical cure between SC and PC antimicrobial therapy. These results further support the IDSA recommendations for a shorter duration of therapy for patients with IAI. DISCLOSURES: All authors: No reported disclosures.