Isolation of trimethoprim-resistant, sulfonamide-susceptible Enterobacteriaceae from urinary tract infections

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Urinary tract infections (UTIs) are common bacterial infections.
• Antimicrobial resistance is a growing global health concern.
• Trimethoprim is a widely used antibiotic for UTIs.

Purpose of the Study:

• To report the emergence of trimethoprim-resistant, sulfonamide-susceptible Enterobacteriaceae causing UTIs.
• To investigate the association between trimethoprim monotherapy and the appearance of these resistant strains.
• To compare the genetic basis of trimethoprim resistance in susceptible versus resistant strains.

Main Methods:

• Bacteriological isolation and identification of Enterobacteriaceae from UTI patients.
• Antimicrobial susceptibility testing for trimethoprim and sulfonamides.
• Plasmid and transposon analysis to determine resistance mechanisms.

Main Results:

• Isolation of trimethoprim-resistant, sulfonamide-susceptible Enterobacteriaceae.
• Correlation between the introduction of trimethoprim alone and the prevalence of these strains.
• Lower frequency of plasmid or transposon-mediated resistance in sulfonamide-susceptible E. coli compared to sulfonamide-resistant strains.

Conclusions:

• Trimethoprim monotherapy can select for resistant Enterobacteriaceae.
• The genetic determinants of trimethoprim resistance may differ based on sulfonamide susceptibility.
• Monitoring antimicrobial resistance patterns is crucial for effective UTI treatment.