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Establishment and Characterization of UTI and CAUTI in a Mouse Model
Published on: June 23, 2015
Virulence factors in uropathogenic E. coli
S N Shrikhande1, C A Chande, A A Pathak
1Department of Microbiology, Govt. Medical College, Nagpur, M.S., India.
Indian Journal of Pathology & Microbiology
|June 22, 2000
Summary
Uropathogenic Escherichia coli strains show increased adherence to uroepithelial cells and mannose-resistant hemagglutination compared to fecal strains. Serogroup O4 was the most frequent among these virulent E. coli.
Area of Science:
- Microbiology
- Infectious Diseases
- Urology
Background:
- Escherichia coli (E. coli) strains causing urinary tract infections (UTIs) possess distinct virulence factors compared to fecal strains.
- Key virulence factors include adherence to uroepithelial cells, lipopolysaccharide O antigen type, and mannose-resistant hemagglutination.
Purpose of the Study:
- To investigate and compare the adherence and hemagglutination properties of E. coli strains isolated from UTIs versus healthy fecal samples.
- To identify common E. coli serogroups associated with urinary tract infections.
Main Methods:
- Studied 100 E. coli strains from symptomatic UTIs and control fecal samples.
- Assessed adherence to uroepithelial cells and hemagglutination of human erythrocytes.
- Determined mannose resistance of hemagglutination and identified E. coli serogroups.
Main Results:
- 58 uropathogenic E. coli strains exhibited high adherence to uroepithelial cells; 28 showed moderate adherence.
- 70 uropathogenic strains induced hemagglutination, with 32 showing D-mannose resistance.
- Control fecal strains showed significantly lower adherence and mannose-resistant hemagglutination (1 of 28).
- Serogroup O4 was most frequent (12%) in uropathogenic isolates, followed by O101, O135, and O6.
Conclusions:
- Uropathogenic E. coli strains possess enhanced adherence and hemagglutination capabilities, indicating their role in UTI pathogenesis.
- Specific E. coli serogroups, particularly O4, are frequently associated with urinary tract infections.
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