Long-Term Trends in Antimicrobial Resistance Among Gram-Negative Clinical Isolates at Mubarak Al-Kabeer Hospital,...

To examine the long-term trends in antimicrobial resistance (AMR) among major Gram-negative pathogens including Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa collected from inpatient and outpatient specimens in Mubarak Al-Kabeer Hospital in Kuwait from 2007 to 2022.

The antimicrobial resistance data for 39,200 non-duplicate Gram-negative isolates were collected from the Hospital Laboratory Information System (LIS). Retrospectively antibiotic susceptibility data were interpreted according to Clinical and Laboratory Standards Institute (CLSI) breakpoints with intermediate results classified as resistant. Logistic regression was applied to assess temporal trends in resistance for the following antibiotic cefotaxime, ceftazidime, ciprofloxacin, meropenem and imipenem. False discovery rate (FDR) correction was performed for multiple comparisons.

Third-generation cephalosporin resistance increased significantly, from 27% to 60% in Klebsiella pneumoniae and from 19% to 45% in Escherichia coli. Resistance to ciprofloxacin also increased, from 22% to 49% in K. pneumoniae and from 28% to 41% in E. coli. Notably, meropenem resistance in K. pneumoniae increased from 1% to 35% during the study period. Acinetobacter baumannii showed high resistance to most antibiotics (>75%), while colistin retained good activity (<2% resistance). By contrast, Pseudomonas aeruginosa showed relatively stable resistance patterns with only modest changes in susceptibility to key antibiotics.

From 2007 to 2022, increasing resistance among major Gram-negative pathogens was observed, with cefotaxime resistance rising from 27% in 2007 to 60% in 2022 in Klebsiella pneumoniae and from 19% to 45% in Escherichia coli. Resistance to ciprofloxacin also increased over time. These findings highlight the increasing burden of antimicrobial resistance over time and emphasize the need for continued surveillance.