Biofilm and Extended Spectrum Beta Lactamase Production amongst Uropathogenic Escherichia Coli Isolates at the University of Ilorin Teaching Hospital, Nigeria

Uropathogenic Escherichia coli (UPEC) are considered major reservoir for genes encoding antimicrobial resistance. The mechanism of resistance and persistence of UPEC has been attributed to the production of biofilm and Extended Beta Lactamase (ESBL). This hospital-based prospective study determined how biofilm and ESBL production facilitate antibacterial resistance amongst UPEC isolated from catheter urine of patients attending the University of Ilorin Teaching Hospital, Nigeria.

Urine samples from 113 catheterized inpatients and outpatients were analysed. Female subjects accounted for 47 (41.6%) of the study population. Standard microbiological methods and Analytical Profile Index (API) 20E were used for the isolation and identification of UPEC. Tissue culture plate technique was used to demonstrate biofilm production potentials and double-disc synergy test was used to determine ESBL production.

Catheter associated urinary tract infection in this study was 70.8% of samples analysed. Of this, Escherichia coli, 44 (55.0%) was the most predominant. UPEC, biofilm and ESBL production amounted to 38.9%, 81.8% and 27.2%, respectively. ESBL production was significantly associated with degree of biofilm formation (p<0.005). Both strong and moderate biofilm producers showed the same level of resistance to ceftazidime (31.6%). Moderate biofilm producers were 46.7% resistant to cefriaxone. Resistance to Amoxillin-clauvanate significantly occurred in all grades of biofilm producers (p>0.05). Imipenem, however, was the most sensitive with no resistance by the UPEC.

ESBL and biofilm production were associated with antibacterial resistance. The incidence of ESBL production amongst biofilm forming UPEC is of great public health concern.