Biofilm Formation by Escherichia coli Isolated from Urinary Tract Infections from Aguascalientes, Mexico

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Uropathogenic Escherichia coli (UPEC) are a primary cause of urinary tract infections (UTIs).
• UPEC biofilms enable bacterial persistence, leading to recurrent infections and severe complications.
• Understanding UPEC's microbiological features is crucial for effective UTI management.

Purpose of the Study:

• To analyze biofilm production, antimicrobial susceptibility, virulence factors, and phylogenetic groups in UPEC strains from UTI patients.
• To determine the relationship between UPEC's microbiological characteristics and its biofilm-forming capabilities.
• To investigate correlations between antibiotic resistance, patient demographics, and biofilm formation.

Main Methods:

• Analysis of 74 E. coli isolates from UTI patients.
• Assessment of biofilm production using optical density (OD) measurements.
• Evaluation of antimicrobial susceptibility to various antibiotics.
• Detection of virulence genes (e.g., fimH, papC, yfcV) and phylogenetic grouping.

Main Results:

• All tested UPEC strains demonstrated biofilm formation capabilities.
• Higher ceftazidime resistance was observed in hospital-acquired UTIs.
• Multidrug resistance and the yfcV gene were more prevalent in male patients (p=0.0017, p=0.0193).
• Strong biofilm formation correlated significantly with the presence of fimH and papC genes, and production of type 1 fimbriae, curli, and cellulose.
• Significant associations were found between higher ODs and resistance to cefazolin, ceftazidime, and cefepime.

Conclusions:

• UPEC's ability to form biofilms is a key factor in UTI pathogenesis and persistence.
• High antibiotic resistance in UTIs, especially in males, may be linked to strong biofilm production.
• Targeting biofilm formation presents a potential strategy for controlling UPEC infections.