Virulence characteristics and antimicrobial susceptibility of uropathogens from patients on Phuket Island, Thailand

Area of Science:

• Medical Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Urinary tract infections (UTIs) are highly prevalent globally.
• Escherichia coli and Klebsiella pneumoniae are leading causes of UTIs.
• Understanding local antimicrobial resistance patterns is crucial for effective treatment.

Purpose of the Study:

• To investigate the antimicrobial susceptibility of E. coli and K. pneumoniae isolates from Phuket Island, Thailand.
• To identify the prevalence of extended-spectrum beta-lactamase (ESBL) production and urovirulence genes in these pathogens.
• To provide data for guiding UTI treatment strategies in Southern Thailand.

Main Methods:

• Collection of 113 E. coli and 52 K. pneumoniae isolates from three hospitals on Phuket Island.
• Antimicrobial susceptibility testing using standard antibiotic panels.
• Detection of extended-spectrum beta-lactamase (ESBL) production.
• Screening for common urovirulence genes (pap, afa, hlyA) in E. coli isolates.

Main Results:

• High resistance rates observed: E. coli (77% to tetracycline, 65% to cotrimoxazole) and K. pneumoniae (65% to tetracycline, 65% to cefotaxime).
• Low resistance to nitrofurantoin (1%) in E. coli.
• Prevalence of ESBL producers: 46% in E. coli and 57% in K. pneumoniae.
• Urovirulence genes detected in 27 E. coli isolates, primarily from internal medicine patients.
• A rare, multidrug-resistant Klebsiella ozaenae isolate identified in a catheterized patient.

Conclusions:

• Significant antimicrobial resistance, particularly to tetracycline and cefotaxime, is present in E. coli and K. pneumoniae causing UTIs in Southern Thailand.
• Nitrofurantoin demonstrates high efficacy against E. coli, suggesting its utility in empirical treatment.
• The findings highlight the need for local surveillance and updated treatment guidelines for UTIs in the region.