2334. Risk Factors of Multidrug-Resistant Gram-Negative Bacterial Bloodstream Infections in Children’s Hospitals in Japan

BACKGROUND: Although multidrug-resistant (MDR) Gram-negative bacilli (GNB) are a serious and growing concern worldwide, the epidemiological data on children are still limited. Our aim was to evaluate the risk factors for MDR GNB bloodstream infections (BSI) in children. METHODS: Patients with GNB BSI were enrolled between April 2010 and March 2017 at eight children’s hospitals in Japan. Clinical and microbiological data were collected retrospectively. The 2012 criteria of the Centers for Disease Control and Prevention were used to define MDR. MDR and non-MDR GNB BSI were then compared in terms of risk factors. RESULTS: In total, 629 GNB BSI cases were identified. The median age and proportion of males was 2 years (IQR 0.3–8.7) and 50.7%, respectively. Underlying diseases were found in 94% of the patients. The proportion of GNB BSI cases developing after >48 hours from admission was 76.2%. The most common GNB was Escherichia coli (29.3%, 184/629), followed by Klebsiella pneumoniae (19.7%, 124/629) and Pseudomonas aeruginosa (16.4%, 103/629). MDR comprised 24.5% (154/629) of cases. The MDR rate for E. coli, K. pneumoniae, and P. aeruginosa was 44.0% (81/184), 23.4% (29/124), and 16.5% (17/103), respectively. The coverage rate of the initial empiric therapy for the MDR and non-MDR GNB BSI cases was 60.4% and 83.4%, respectively (P < 0.001). The all-cause mortality rate at 28 days of GNB BSI was 10.7% (67/629), 13.6% (21/154), and 9.7% (46/475) for MDR- and non-MDR GNB BSI, respectively (P = 0.167). The all-cause mortality rate at 28 days was 10.4% (14/135) and 7.7% (27/351) for MDR and non-MDR Enterobacteriaceae BSI (P = 0.341) and 41.2% (7/17) and 18.6% (16/86) for MDR- and non-MDR P. aeruginosa BSI, respectively (P = 0.056). Multivariate logistic regression analysis showed that MDR GNB BSI was independently associated with anticarcinogenic drug use within 30 days (OR: 43.90; 95% CI: 4.69–411.08), older age (OR: 1.05; 95% CI: 1.02–1.09), and admission to the neonatology ward (OR 0.019; 95% CI: 0.005–0.076). CONCLUSION: One-fourth of GNB BSI cases were MDR. Anticarcinogenic drug use and older age were risk factors for MDR GNB BSI in children’s hospitals. MDR P. aeruginosa infections were associated with higher all-cause mortality. DISCLOSURES: All authors: No reported disclosures.