1206. Epidemiological interaction of MRSA, ESBL E.coli and C. difficile between ICU/Step-down Unit of University-affiliated Community Hospital and LTACs in Japan: Utility of Molecular Epidemiology Analysis by PCR-based ORF Typing (POT method)

• Published in: Open forum infectious diseases Vol. 9; no. Supplement_2
• Main Authors: Saito, Hiroki, Kasai, Fumimasa, Takakura, Tomomi, Ohno, Tatsuya, Hosoyama, Akiko, Fujitani, Shigeki
• Format: Journal Article
• Language: English
• Published: 15.12.2022
• ISSN: 2328-8957; 2328-8957
• DOI: 10.1093/ofid/ofac492.1039

Abstract Background Epidemiological interaction of drug resistant organisms between ICU and surrounding health facilities including LTACs have been of interest in the era of antimicrobial resistance (AMR) and aging society. In addition, conventional molecular epidemiology methods such as pulsed-field gel electrophoresis, and multilocus sequence typing are time-consuming and difficult to perform in a standard microbiology laboratory. Methods Patients admitted to a university-affiliated community hospital in Japan was recruited if their cultures collected clinically during admission grew the following target pathogens: Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin Resistant Enterococci (VRE), ESBL Gram negative rods (GNR), carbapenem-resistant Enterobacteriaceae (CRE), multi-drug resistant Pseudomonas (MDRP) and Clostridioides difficile (C. diff). Their clinical information including admission to ICU/step-down unit vs regular wards and disposition was analyzed with chi-square test for binary outcomes. For the isolates of MRSA, ESBL E. coli, and C. diff, further molecular epidemiology analysis was made, using PCR-based open-reading frame (ORF) Typing (POT method), a more resource-friendly and time-efficient technology originally developed in Japan. Results Among total 9639 hospital admissions in 2018-2019, the above-mentioned target pathogens grew from 233 patients (2.4%). There were 96 MRSA isolates (41.2%, out of 233), followed by 93 ESBL GNR (39.9%), 21 C. diff (9.0%), 13 CRE (5.6%), 10 MDRP (4.3%), and no VRE, respectively. Patients admitted to ICU/step-down unit were more likely to grow the target pathogens (117/1605 vs 116/7801, RR 4.90, 95% CI 3.81-6.30, p< 0.001), and to be discharged to LTACs than patients admitted to regular wards (70/113 vs 32/116, RR 2.17, 95% CI 1.56-3.02). Molecular epidemiology analysis with POT method identified 5, 3 and 3 common strains across 20, 11, and 7 patients with MRSA, ESBL E.coli, C. diff, respectively. Conclusion The study suggests the pathogens of higher priority were more prevalent in ICU/step-down unit and that the discharge from ICU/step-down unit to LTACs could impact on further transmission in the surrounding region. POT method can be utilized for more efficient molecular epidemiology analysis in the era of AMR. Disclosures All Authors: No reported disclosures.