TITLE:
Trends in Antimicrobial Resistance Mechanisms and Susceptibility among Enterobacterales in Hospitalized Patients: A Single Center Microbiological Clinical Analysis 2010-2025
AUTHORS:
Jamal Wadi Al Ramahi
KEYWORDS:
ESBL-PE, CRE, AmpC-Producers, SHV1, Carbapenemases
JOURNAL NAME:
Advances in Infectious Diseases,
Vol.16 No.3,
September
2,
2026
ABSTRACT: Background: To evaluate trends in antimicrobial resistance mechanisms among Enterobacterales over a sixteen-year period. Methods: Data for Enterobacterales isolates were extracted from a VITEK® 2 Compact system database. Trends, resistance mechanisms, and susceptibilities were analyzed for extended-spectrum β-lactamase (ESBL), carbapenem-resistant Enterobacterales (CRE), and AmpC-producing strains. Phenotypic resistance patterns were checked manually for selected strains to ensure interpretation consistency. Results: A total of 20,266 Enterobacterales isolates were analyzed, comprising Escherichia coli (n = 12,783; 63.1%), Klebsiella (n = 4,302; 21.2%), Enterobacter (n = 1,060; 5.23%), Proteeae (n = 1,426; 7.04%), Citrobacter (n = 391; 1.93%), and Serratia (n = 304; 1.5%). The overall prevalence of ESBL-producing Enterobacterales (ESBL-PE) was 29.8%, E. coli 47.0%, Klebsiella 36.0%, and 5.3% for Proteeae. AmpC production was observed in 13.9% as an overall, for Enterobacter 25.0%. Klebsiella 18.0%, Serratia 19%, E. coli 13%, Citrobacter 9.0%, and 6.0% of Proteeae. SHV-1 hyperproduction was identified in 8.85%, E. coli 13.0%, and 1.9% of Klebsiella. The overall prevalence of CRE was 22.4%, of which carbapenemase production was detected in 25.0% of Klebsiella, Enterobacter 11%, Serratia 5.3%, Citrobacter 4.9%, E. coli 3.0%, and 2.3% of Proteeae. Porin impermeability was found in 20.3% of Klebsiella, Enterobacter 10.1%, and 2.5% of E. coli. Metallo-β-lactamases (MβLs) or K. pneumoniae carbapenemase (KPC) expression was present in 2.4% of Klebsiella, and Enterobacter, E. coli and Citrobacter. TEM-or-OXA mediated resistance was noted in Klebsiella 17.0%, E. coli 16%, and 11.0% of Proteeae. Conclusion: Trends for ESBL-PE, CRE, AmpC-producers, and SHV-1 hyperproducers showed minimal chronological changes over the 16-year period, which were not clinically significant (OR = 1.0, P