O-11 An emerging threat; microbiological profiles and antimicrobial susceptibility patterns of carbapenem-resistant enterobacterales identified at Georgetown Public Hospital Corporation, 2023–2025
Author(s):
J Ramah, A Wilson, P Mohamed -Rambarran
Year of Presentation:
2026
Objective: Carbapenem-Resistant Enterobacterales (CRE)
have emerged as a major global public health threat due to
their high levels of antimicrobial resistance and association
with adverse clinical outcomes. The objectives of this study
were to describe demographic profiles, to characterize the
antimicrobial susceptibility profiles of CRE isolates, and
to identify the carbapenem resistance mechanisms present
among CRE isolates at Georgetown Public Hospital Corporation between 2023 and 2025.
Methods: A retrospective cross-sectional study was conducted using microbiology laboratory records from January 2023 to December 2025. All non-duplicate Enterobacterales isolates demonstrating resistance to at least one carbapenem (imipenem or meropenem) based on CLSI criteria were included. Data collected included patient demographics, hospital ward, specimen source, bacterial species, antimicrobial susceptibility results, and carbapenemase mechanisms detected using the Rosco Diagnostica rapid diagnostic kit. Descriptive statistics were used for analysis. A total of 83 samples were analyzed.
Results: A total of 83 CRE isolates were identified. Most patients were aged ≥50 years (48.2%), and males predominated (73.5%). The highest number of isolates originated from medical wards and intensive care units. Urine was the most common specimen source (28.9%), followed by wound and blood samples. Acinetobacter baumannii (42%) and Klebsiella pneumoniae (30%) were the most frequently isolated organisms. All isolates demonstrated non-susceptibility to carbapenems, with high resistance rates to thirdgeneration cephalosporins and fluoroquinolones. Fosfomycin retained the greatest activity, with 36% of isolates remaining susceptible. Molecular testing revealed exclusive New Delhi metallo-β-lactamase (NDM)-mediated resistance in all isolates, with no detection of KPC, VIM, or OXA-48-like enzymes.
Conclusion: CRE at GPHC exhibit extensive antimicrobial resistance driven by exclusive NDM-mediated carbapenemase production, leaving very limited treatment options. Inclusion of aztreonam and ceftazidime/avibactam in the formulary is recommended alongside strengthened infection prevention and control, routine CRE surveillance, and robust antimicrobial stewardship.