Biofilm formation by ESBL-producing uropathogenic E. coli

Abstract

Introduction: E. coli is considered to be the leading cause of urinary tract infections. (UTIs) and is responsible for both community acquired and hospital acquired UTIs. The ability of this bacterium to form biofilm on various devices like catheters plays an important role in progression of the disease. Biofilm production in extended spectrum beta lactamases (ESBLs) producing organisms provides a favourable environment for the exchange of resistance genes and may also facilitate widespread dissemination.
 Methods: The urine samples were collected from the suspected cases of urinary tract infections and were cultured on cystine lactose electrolyte deficient (CLED) agar plates to isolate the desired UPEC strains. All the isolated E. coli strains were subjected to ESBL detection by double disk approximation method and to biofilm formation by tissue culture plate method of biofilm detection. All the results were statistically analysed using k2 test with p value at <0.05 level of significance.
 Results: Out of all the gram negative bacilli isolated from urine samples, E. coli alone accounted for 90% of the isolates. Of all the UPEC isolates subjected to ESBL detection 50% of the strains turned out to be the ESBL producers and 35% of the strains showed biofilm formation.
 Conclusion:
 
 The majority of the work in literature sites the data samples collected from indoor patients, where these isolates coli strains which produced ESBLs were mainly a strong biofilm former as compared to non-ESBL producer strains.
 In this study in spite of all the coli strains being outpatient isolates still the correlation between ESBL production and biofilm formation holds true.
 We found a significant correlation between biofilm formation and ESBL production. The detection of ESBL production and biofilm formation pattern will help in development of newer and more effective treatment.