Abstract
OBJECTIVE: We sought to analyze the characteristics of pathogenic bacteria in urinary tract infections (UTIs) samples and to measure their resistance to antibiotics in different period of coronavirus disease 2019 (COVID-19) epidemic. METHODS: We retrospectively analyzed changes in the distribution of pathogenic bacteria in UTIs samples as well as their antimicrobial resistance during 2019-2023. We compared the distribution of these pathogens and their antimicrobial resistance before (1/2019-1/2020), during (2/2020-3/2022), and after (4/2022-12/2023) the COVID-19 pandemic. The results obtained were interpreted with reference to Clinical and Laboratory Standards Institute (CLSI M100, 33rd ed., 2023) and analyzed with WHONET 5.6 software. RESULTS: From 2019 to 2023, a total of 19,038 urine bacterial culture samples, of which 3044 were positive, accounting for 15.99%. Positive cultures were most common in individuals aged ≥ 60 years (accounted for over 50%), and drug-resistant strains were also more commonly found in the elderly (accounted for over 57.49%). The top four most common urinary pathogens were Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis and Enterococcus faecium. Escherichia coli resistance to ampicillin remained highest. During the COVID-19 pandemic, Klebsiella pneumoniae demonstrated higher resistance levels to antimicrobial agents including ceftazidime (15.63%-33.33%-17.31%), aztreonam (25.00%-41.94%-28.85%), and cefepime (28.13%-50.54%-34.62%) compared to pre-pandemic and post-pandemic periods, and Klebsiella pneumoniae exhibited resistance rates exceeding 30% for both ampicillin/sulbactam and cefazolin throughout the study period. Susceptibility rates exceeding 78% were demonstrated in Enterococcus faecalis and Enterococcus faecium toward nitrofurantoin, vancomycin, and linezolid. Furthermore, the proportion of drug-resistant strains of Enterococcus faecalis and Enterococcus faecium increased from 61.36% to 77.14% in the pre-pandemic period to 63.41% and 90.00% in the post-pandemic period, respectively. The increase in the proportion of drug-resistant strains was more pronounced in Enterococcus faecium than in Enterococcus faecalis. CONCLUSION: The main pathogens of UTIs were Escherichia coli. Changes in UTIs risk and antibiotic resistance may be associated with the COVID-19 pandemic. Meanwhile, we have observed a gradual increase in antibiotic resistance among certain pathogens. Therefore, to ensure optimal therapeutic efficacy, antimicrobial susceptibility testing and bacterial culture should be performed prior to antibiotic administration, thus ensuring rational and effective use.