1110. A multicenter Evaluation of Outcomes Associated With Oral Vancomycin Dose in Patients With Clostridium difficile Infection

BACKGROUND: Clostridium difficile infection (CDI) is a significant cause of morbidity and mortality. IDSA guidelines recommend oral vancomycin (VAN) for the treatment of CDI, although doses used in practice vary substantially. The purpose of this study was to determine differences in outcomes between patients treated with high dose (HD; ≥250 mg four times daily [QID]) vs. standard dose (SD; 125 mg QID) VAN for CDI. METHODS: This multicenter study evaluated patients at two hospitals in Albany, NY diagnosed with CDI and treated with oral VAN between January 2013 and August 2017. Hospitalized patients were included if: age ≥18 years, positive C. difficile toxin polymerase chain reaction (PCR), symptomatic infection (e.g., new onset or increased frequency of loose stools), and received ≥48 hours of VAN QID. Patients were excluded if: received ≥48 hours of metronidazole prior to VAN initiation, VAN per rectum, required surgical intervention ≤48 hours from PCR, had a history of fecal microbiota transplant, received ≥1 dose of fidaxomicin or tigecycline prior to or within 48 hours from PCR, or died ≤48 hours from PCR. The primary outcome was 90-day CDI recurrence; secondary outcomes included 30-day all-cause mortality and 90-day readmission. Variables with a P-value <0.2 in univariate analysis were evaluated in multivariate (MV) analyses. RESULTS: Four hundred fifty-eight patients were included (site 1: 270; site 2: 188). Two hundred twenty-four patients received SD VAN (48.9%); 234 received HD VAN [250 mg QID: 199 (43.5%); 500 mg QID: 35 (7.6%)]. Baseline demographics were similar between groups. Patients treated with HD were more likely to present with colitis (19.2 vs. 29.5%, P = 0.01) and have higher infection severity based on IDSA (P < 0.01), Zar (P < 0.01), and American College of Gastroenterology (P < 0.02) criteria. Modified APACHE II scores were similar between SD and HD groups (median: 12.2 vs. 12.9, P = 0.17). MV analysis identified no difference in 90-day recurrence with HD (OR 1.65, P = 0.13) after controlling for solid tumor cancers, immunosuppression, and IDSA severity. Similarly, no significant differences between SD and HD were observed for 30-day mortality and 90-day readmission. CONCLUSION: No differences in recurrence, mortality, or readmission were identified between SD and HD oral VAN for the treatment of CDI, though HD VAN patients primarily received 250 mg QID. DISCLOSURES: All authors: No reported disclosures.