Related Experiment Videos
Changes in the antibiotic sensitivities of urinary pathogens, 1971-1989
1Department of Clinical Microbiology, University College Hospital, London, UK.
Abstract:
All urinary pathogens from general practice and hospital have been tested for sensitivity to a range of antimicrobial agents for the last 19 years. There have been marked changes during that time. In general practice there has been a considerable increase in the proportion of staphylococcal infections from 5.1% to a peak of 14.8% in 1982 and a more recent decline to 3.4%. There has also been a decrease in the proportion caused by Proteus mirabilis, from 9.2% to 5.0%. Similar, but smaller changes have been observed in the proportions of hospital urinary tract infections (UTI) caused by these organisms, while the proportion of hospital infections due to Klebsiella spp. and Enterobacter spp. has fallen from 16.8% to 9.2%. These and other changes have been reflected in changing patterns of sensitivity to antibiotics. In particular, sensitivity of urinary pathogens to ampicillin/amoxycillin has continued to fall both in general practice and in hospital. Nalidixic acid resistance is becoming more important as the proportion of Gram-positive urinary pathogens (especially enterococci) increases. More organisms were sensitive to ciprofloxacin than the other drugs tested, with no evidence of increasing resistance over a six-year period. Over the same time there has been a reduction of overall sensitivity of urinary pathogens to trimethoprim from 90.8% to 82.5% in general practice, with no significant change in isolates from hospital practice.
Insights
Antimicrobial resistance in urinary pathogens has shifted over 19 years. Ciprofloxacin remains effective, but resistance to ampicillin/amoxycillin and trimethoprim is increasing, especially in general practice settings.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Antimicrobial Stewardship
Background:
- Urinary tract infections (UTIs) are common, with pathogens varying between community and hospital settings.
- Long-term surveillance of antimicrobial sensitivity is crucial for effective treatment strategies.
- Changes in pathogen prevalence impact antibiotic efficacy.
Purpose of the Study:
- To analyze 19 years of antimicrobial sensitivity data for urinary pathogens.
- To identify trends in pathogen prevalence and antibiotic resistance in general practice and hospitals.
- To inform optimal antibiotic selection for UTIs.
Main Methods:
- Retrospective analysis of antimicrobial sensitivity testing data for urinary pathogens.
- Data collected over a 19-year period from general practice and hospital sources.
- Tracking changes in the proportion of specific pathogens and their sensitivity to various antibiotics.
Main Results:
- Significant shifts in pathogen proportions observed, including increased Staphylococcus in general practice and decreased Proteus mirabilis.
- Hospital UTI proportions showed changes in Klebsiella spp. and Enterobacter spp.
- Declining sensitivity to ampicillin/amoxycillin and trimethoprim noted, while ciprofloxacin demonstrated sustained efficacy.
- Increasing nalidixic acid resistance correlated with a rise in Gram-positive pathogens like enterococci.
Conclusions:
- Antimicrobial resistance patterns for urinary pathogens have evolved significantly over two decades.
- Ciprofloxacin remains a reliable option, unlike ampicillin/amoxycillin and trimethoprim, which show decreasing effectiveness.
- Monitoring resistance trends is essential for guiding empirical antibiotic therapy in UTIs.