Twenty-one multiresistant Enterobacter cloacae isolates producing OXA-48 (n = 10), CTX-M-15 (n = 7) or both (n = 4) ␤-lactamases were detected in a Spanish hospital during a 1-year period (June 2013 to June 2014). The isolates were also resistant to non-␤-lactam antimicrobials, further complicating the therapeutic options. Genotyping of the isolates identified two major clones (ST74 and ST66) that caused prolonged outbreaks in different buildings of the hospital as well as some sporadic isolates (ST78, ST45 and ST295). Isolates belonging to clone 1 (n = 7) were carbapenem-resistant and carried the bla OXA-48 gene on a conjugative IncL/M plasmid of ca. 65 kb. Clone 2 isolates (n = 11) were resistant to cefepime and harboured the bla CTX-M-15 gene on an ca. 150-kb, non-conjugative plasmid of the IncF group, co-harbouring the qnrB and aac(6 )-Ib-cr genes encoding quinolone resistance. Four clone 2 isolates were also resistant to carbapenems owing to the co-production of OXA-48. Most of the isolates were recovered from critically ill patients and were admitted to intensive care units; a single patient was transferred from another Spanish hospital. Intrahospital and interhospital dissemination of multiresistant E. cloacae isolates is of major clinical concern as it could lead to endemic nosocomial situations.

Background Background: Pseudomonas aeruginosa continues to be an important cause of nosocomial infections associated with a high morbidity and mortality. Despite the availability of ceftazidime-avibactam (CAZ-AVI) and ceftolozone-tazobactam (CFT-TAZO), CEF continues to be an empiric agent of choice in several institutions. Aim: To evaluate the prevalence and trend in susceptibilities of P. aeruginosa to CEF over a 7-year period, identify possible correlation with the use of CAZ, AZT, PTZ, CIP, and CAR, (DOT/1000 patient days), as a quality improvement (QI) measure for optimizing CEF use, introduce antibiotic cycling as a tool to avoid emergence of drug-resistance in P. aeuriginosa. Methods A retrospective review of antimicrobial susceptibility data of all isolates of P. aeruginosa, (inpatient and outpatient) at the Detroit VAMC pre and post implementation of antibiotic cycling, over a 7-year period (2011-2017) was performed. Susceptibility testing was performed by reference broth micro-dilution methods in a central laboratory. Data analysis was performed using Pearson correlation coefficient score. Being a QI project, clinical data were not reviewed. Results A total of 977 isolates were identified during the study period. (drug usage are in DOT/1000 PD); CAZ and AZT use surged during 2013-14 from 5 to 8 dropping in 2015-17 to < 3; PTZ usage increased to 100 during 2011-14 but dropped to 38 in 2015-17 (drug shortage); CAR use averaged at 10 until 2016 and dropped to 8 in 2017; CIP use dropped by 50% from 30 in 2012 to 15 in 2017; P. aeruginosa susceptible to CEF decreased from 88% in 2012 to 81% in 2014 mirroring the increased use of CEF, AZT, CAZ, and CIP; AG use was very low at < 5. With restrictions on the use of AZT, CAZ, and CIP, from 2014-15, CEF susceptibility increased significantly to 95.5% in 2015. Drug shortage of PTZ in 2015 and increased use of CEF from 2015-17 led to a drop in susceptibility to (82%); P. aeruginosa susceptible to CAR and AG averaged at 88% and 97% respectively (2011-17). However, reintroduction PTZ, resulted in improved susceptibility of P. aeuruginosa to CEF by 40% within a year. Conclusion Judicious antimicrobial use and antibiotic rotation play a significant role in reversing drug resistance in P. aeuruginosa. Disclosures All Authors: No reported disclosures

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Background Ultraviolet (UV) light disinfection following a manual terminal cleaning process for hospital rooms has been proposed as an additional method to reduce the bacterial burden on surfaces. The impact of UV light disinfection and the level of interdependence between the modalities remains unclear. Methods Samples were collected from 5 high touch surfaces from 10 patients room following discharge prior to manual disinfection, following manual disinfection, and following pulsed xenon UV disinfection using Rodac contact plates (total 150 samples). Colonies were identified using MALDI-TOF mass spectrometry. The bacterial colony counts were recorded and analyzed as pathogenic or commensal organisms (based on CDC criteria) to assess the efficacy of the disinfection process. Results Average colony counts for the rooms prior to disinfection, post disinfection, and post UV light were 185.8 CFU +/- SD 280, 43 CFU +/- 121, and 20 CFU +/- 36.7 respectively. The average drop in colony-forming units of the five high touch areas in patient’s rooms can be seen in table 1. Twelve commensal bacterial species were isolated: Bacillus species (sp.), Corynebacterium sp., Enhydrobacter sp., Kocuria sp., Lysinibacillus sp., Macrococcus sp., Micrococcus sp., Paenibacillus sp., Pantoea sp., Psychrobacter sp., Siccibacter sp., Coagulase negative staphylococcus. Seven pathogenic bacteria were isolated: Acinetobacter sp., Brucella sp., Proteus sp., Staphylococcus aureus, Escherichia sp., Enterococcus, and Pseudomonas aeruginosa. Reductions in the predominant bacterial species following disinfection modality are noted in table 2. Table 1: Colony forming units (CFUs) average Pre-disinfection (Pre-Dis), Post Disinfection (Post-Dis), and Post PX-UV Light (PX-UV). Table 2: Sub-analysis of commensal and pathogen isolation Pre-Disinfection (Pre-Dis), Post-Disinfection (Post-Dis), and Post PX-UV light (PX-UV). Conclusion A combination of manual disinfection and UV has shown a notable additional reduction in overall bacterial contamination of the patient rooms, including the majority of high touch areas as compared with manual disinfection alone. No additional reduction in commensal bacteria isolates was noted after UV light, however a further decrease in pathogenic bacteria (Acinetobacter and Enterococcus) was noted. UV light may be considered as an additional room disinfection method to reduce overall bacterial burden and pathogenic bacterial contamination of rooms as a comprehensive strategy to reduce nosocomial infections. Disclosures Mark Stibich, n/a, Xenex Germ-Zapping Robots (Board Member, Grant/Research Support) Chetan Jinadatha, MD, MPH, AHRQ (Research Grant or Support)Department of Veterans Affairs (Other Financial or Material Support, Owner: Department of Veterans Affairs. Licensed to: Xenex Disinfection System, San Antonio, TX)Inventor (Other Financial or Material Support, Methods for organizing the disinfection of one or more items contaminated with biological agents)NiH/NINR (Research Grant or Support)NSF (Research Grant or Support)Xenex Healthcare Services (Research Grant or Support)