Abstract
Introduction
Antimicrobial resistance (AMR) is an emerging global health threat, particularly in low- and middle-income countries where healthcare resources are limited and where antibiotic misuse is widespread. In Cambodia, AMR poses a severe challenge, with increasing resistance among pathogens responsible for bloodstream infections (BSIs) and bacterial meningitis. Key bacterial pathogens, including Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Acinetobacter spp., and Streptococcus pneumoniae, exhibit high levels of resistance, presenting substantial treatment challenges. The emergence of extended-spectrum beta-lactamases (ESBLs), carbapenemases, and methicillin-resistant S. aureus (MRSA) exacerbates the AMR crisis. This study aimed to examine the bacterial profiles and AMR patterns of different bacterial pathogens.
Methods
A retrospective analysis was conducted using data collected from the National AMR Surveillance System between 2018 and 2021 (CamLIS). It included bacterial isolates from mostly blood and cerebrospinal fluid samples processed at eight sentinel hospitals, including Siem Reap, Battambang, Takeo, and Kampong Cham Provincial Referral Hospitals, and National Pediatric Hospital, Calmette Hospital, Angkor Hospital for Children, and Hope Center of Sihanouk Hospital. Laboratory testing was conducted to identify bacterial isolates and AMR patterns across pathogens. Antimicrobial susceptibility testing (AST) was performed. After cleaning and checking, 38978 records remained. Descriptive analysis was performed via STATA version 14.2 to calculate the means (SDs) for continuous variables such as age and frequency and percentages for categorical variables such as age group and sex, pathogen identification, susceptibility results, and AMR patterns.
Results
Escherichia coli was the most frequently isolated pathogen (40.5%), followed by Klebsiella pneumoniae, Acinetobacter spp., Staphylococcus aureus, and Streptococcus pneumoniae. The highest prevalence of infections occurred in patients aged 45–64 years (29.5%), with 21.4% in those over 64 years. The findings revealed 94.4% resistance to ampicillin in E. coli and 39.7% resistance to amoxicillin-clavulanate in K. pneumoniae. Carbapenem resistance was detected in 21.6% of the K. pneumoniae isolates, whereas carbapenem resistance increased in A. baumannii. The MRSA prevalence was 61.3%, with high resistance to erythromycin (69.7%) and clindamycin (69.2%), and S. pneumoniae exhibited significant resistance to penicillin and macrolides.
Conclusion
This study highlights the growing threat of AMR in Cambodia, particularly among E. coli, Klebsiella pneumoniae, and MRSA isolates. Resistance mechanisms such as ESBL production, carbapenemase resistance, and methicillin resistance are widespread, reflecting regional and global trends of AM. Cambodia’s response, including the establishment of the National AMR Surveillance System and the National Action Plan to Combat AMR, represents significant progress. However, geographic disparities in healthcare access, limited laboratory infrastructure, and persistent antibiotic misuse remain major challenges. Strengthening surveillance, enhancing infection control, and promoting responsible antibiotic use are essential to combat AMR effectively.