1499. Distribution and Clinical Implication of Isolation of Multidrug-Resistant Microorganisms in Patients with Intra-Abdominal Infections

BACKGROUND: The aim of this study was to determine the prevalence and the clinical significance of multidrug-resistant microorganisms (MDROs) isolated from patients with intra-abdominal infections. METHODS: This cohort study was conducted at a 1,051-bed university-affiliated hospital in the Republic of Korea, between 2016 and 2018. The subjects included patients with intra-abdominal infections who had identified causative organisms. Patients with spontaneous bacterial peritonitis were not included in our study. Identification and antimicrobial susceptibility testing were done by standard criteria as defined by the Clinical and Laboratory Standards Institute. RESULTS: During the study period, a total of 627 non-duplicated clinical isolates were collected from 430 patients. Among these patients, 196 patients (45.6%) were suffered from generalized peritonitis while 234 (54.4%) affected by localized peritonitis or abscesses. In total, 152 (35.3%) were affected by healthcare-associated infections. The overall mortality and the 28-day mortality rate were 6.3% and 5.8%, respectively. Distribution of causative microorganisms was as follows: aerobic gram-positive (40.5%), aerobic gram-negative (56.1%), anaerobic (1.9%), and fungal (1.4%) pathogens. Escherichia coli (24.2%) was isolated most frequently, followed by Enterococcus spp. (23.9%), Klebsiella spp. (16.3%), and Streptococcus spp. (11.8%). The MDROs represented 15.8% of the total of isolated micro-organisms (figure). In the multivariable logistic regression analysis, isolation of MDROs (odds ratio [OR], 3.72; 95% confidence interval [CI], 1.53–9.04), hypoalbuminemia (OR, 5.56; 95% CI, 1.25–24.75), immunosuppressant (OR, 6.29; 95% CI, 1.96–20.18), and underlying renal diseases (OR, 4.29; 95% CI, 1.66–11.11) were found as independent risk factors for 28-day mortality. CONCLUSION: In conclusion, our study indicates that MDROs are widespread in the patients with intra-abdominal infections. Furthermore, the isolation of MDROs was associated with poor clinical outcomes. For the appropriate selection of empirical antibiotics, local epidemiology of causative microorganisms and patterns of antimicrobial resistance should be continuously monitored. [Image: see text] DISCLOSURES: All authors: No reported disclosures.