Genotypic Characterization of Urinary Tract Infections causing bacteria isolates among Adults at Kiambu Level 5 Hospital, Kenya: Selected Extended Spectrum β-Lactamase genes and Biofilm Formation

Abstract

The menace of antimicrobial resistance to public health is constantly arising globally. Many pathogenic bacteria use mechanisms such as mutations and biofilm formation, significantly reducing antimicrobial agents' efficacy. In this cross-sectional study, we aimed to determine the prevalence of selected extended spectrum β-lactamase (ESβLs) genes and analyse the biofilm formation abilities of the isolated bacteria causing urinary tract infection among adult patients against selected drug dosages seeking Medicare at Kiambu Level 5 Hospital, Kenya. The double-disk synergy test was used for phenotypic identification of ESβLs producing isolates, while microtiter plate assays with some modifications were used for the biofilm formation test. A total of 10 isolates were bioassayed for ESβL genes presence out of 57 bacteria isolates obtained from urine samples. This study found the blaTEM genes to be the most prevalent ESβLs type 10/10 (100%), followed by blaOXA and blaSHV genes at 4/10 (40%) and 3/10 (30%), respectively. In addition, the co-carriage of blaTEM and blaSHV was 50% lower than that of blaTEM + blaOXA genes at 66.7% among the study Escherichia coli isolates. Biofilm formation was positive in 36/57 (63.2%) of the isolates tested, with most being Gram-negative 25/36 (69.4%). Escherichia coli 15/36 (41.7 %), Klebsiella species 7/36 (19.4%), and Staphylococcus aureus 7/36 (19.4%) were the dominant biofilm formers. However, there was no significant difference in biofilm formation among all tested isolates, with all isolates recording p-values above 0.05. In light of these findings, biofilm formation potential coupled with antimicrobial resistance genes in UTI isolates could likely lead to difficult to treat infections.