Reduction of Antimicrobial Resistance among Gram- Negative Pathogens after Antimicrobial Stewardship in Three Tertiary Egyptian Hospitals

BACKGROUND: Antimicrobial resistance is an urgent healthcare threat. Monitoring and interventions to reduce antimicrobial resistance among Gram-negative rods (GNR) are essential. METHODS: The study was conducted over three years in three tertiary- care hospitals in Egypt during 2014- 2016. It included 578 GNR isolates from intra-abdominal infections (IAI), urinary tract infections (UTI) and respiratory tract infections (RTI). Identification of isolates was done by VITEK-2, and confirmed by MALDI-TOF at a central laboratory as part of Study for Monitoring Antimicrobial Resistance Trends (SMART). Susceptibility testing and molecular studies of resistance were conducted in the hospital laboratories. Starting from 2015, an antimicrobial stewardship (AMS) program was implemented in the 3 hospitals for fluoroquinolone restriction in empirical therapy, and early de-escalation of antimicrobial therapy. RESULTS: In Phase 1 (before AMS), 578 isolates of Gram-negative bacilli (GNB) were studied. Enterobacteriaceae comprised 66% of the total isolates. K.pneumoniae and E.coli were the most common (29.8% and 29.4%), followed by Acinetobacter baumannii (21.1%) and P.aeruginosa (9.9%). K.pneumoniae and E.coli were the predominant organisms in IAI (30.5% and 30.1% respectively) and UTI (and 38.9% and 48.6% respectively), while Acinetobacter baumannii was the most prevalent in RTI (40.2%). ESBL producers were phenotypically detected in 53% of K.pneumoniae, 68% of E.coli and 64% of Proteus mirabilis. Amikacin, imipenem, ertapenem and piperacillin/tazobactam had the highest susceptibility (60.7%, 58%, 49.3% and 46.5% respectively). In Phase 2 (after AMS), 492 Gram-negative bacilli (GNB) were studied, showing similar distribution except for marked reduction in Acinetobacter baumannii(5.3% in IAI, 11.4% in RTI and 1% in UTI). ESBL continued to be high. Susceptibility to carbapenems increased to 87.1% for E.coli and 77.7% for all Enterobacteriaceae. PCR showed predominance of OXA-48- like (more than 50% and NDM (more than 40%), with low percentage of KPC2, VIM2 and IMP. CONCLUSION: Our results show high ESBL and carbapenemases rates compared with the region that call for an urgent national AMS program and strict implementation of infection control measures. DISCLOSURES: A. El Kholy, MSD: Investigator, Research support; S. A. Girgis, MSD: Investigator, Research support; M. A. F. Shetta, MSD: Research Contractor, Research support; A. Ramadan, MSD: Investigator, Research support; D. H. AbdElhHamid, MSD: Investigator, Research support