Update on Shigella and Nontyphoidal Salmonella Antimicrobial Drug Resistance: Implications on Empirical Treatment of Acute Infectious Diarrhea in Cambodia

y Information on causative diarrheal pathogens and their associated antimicrobial susceptibility remains limited for Cambodia. This study describes antimicrobial resistance patterns for Shigella and nontyphoidal Salmonella isolates collected in Cambodia over a 5-year period. Multidrug resistance was shown in 98% of Shigella isolates, with 70%, 11%, and 29% of isolates being resistant to fluoroquinolones, azithromycin, and cephalosporin, respectively. As many as 11% of Shigella isolates were resistant to nearly all oral and parenteral drugs typically used for shigellosis, demonstrating extreme drug resistance phenotypes. Although a vast majority of nontyphoidal Salmonella isolates remained susceptible to cephalosporins (99%) and macrolides (98%), decreased susceptibility to ciprofloxacin was found in 67% of isolates, which is notably higher than previous reports. In conclusion, increasing antimicrobial resistance of Shigella and nontyphoidal Salmonella is a major concern for selecting empirical treatment of acute infectious diarrhea in Cambodia. Treatment practices should be updated and follow local antimicrobial resistance data for the identified pathogens.

Automated summary

This study found an increasing trend of multidrug resistance among Shigella and nontyphoidal Salmonella isolates collected in Cambodia, highlighting a major challenge for the selection of treatment options for acute infectious diarrhea in the country. It is crucial for treatment practices to be updated and guided by local antimicrobial resistance data for the identified pathogens.