Efflux Pumps, Biofilm Formation, and Susceptibility Testing of Escherichia Coli Isolated from Urinary Tract Infection

Abstract

Urinary tract infections (UTIs) are infectious diseases of the urinary system caused by several causative agents, including parasites, viruses, fungi and bacteria. The most frequent UTI cause is Escherichia coli (E.coli). Antibiotic resistance in E. coli has been linked to overexpression of the efflux system. This study aimed to isolate various bacteria from UTI and then select E. coli isolates to study the prevalence of the efflux pump genes TetA and MdfA.This study included 150 midstream urine samples from patients suffering from UTI (115 females and 35 males) with ages ranging between(5-70)years. The results showed that only 100 samples exhibited bacterial growth; 72.5% referred to female patients, while 27.5% referred to male patients. Infection with bacteria occurred most frequently in the age group of 21-30 years. Bacterial isolates were identified by macroscopic and microscopic examination, biochemical test and VITEK2 system. The result showed that 40% of these growth were confirmed to be E.coli,19% Klebsiella pneumonia,17% Staph.aureus, 13%Proteus mirabilis,7% Pseudomonas aeroginosa, 2% Staph. saprophyticus,1%Proteus vulgaris and 1%Enterobacter cloaca.The results of sensitivity to antibiotics showed that UPEC isolates were utterly resistant to novobiocin and rifampin 100%, ampicillin 87.5%, cefotaxime 85%, tetracycline82.5%, ciprofloxacin77.5%, trimethoprim-sulfamethoxazole 50%, gentamicin 22.5%, nitrofurantoin 17.5% and meropenem 2.5%. All of the isolates were multidrug resistant. The result of the biofilm-formation ability of E.coli isolates showed that 31/40(77.5%) of isolates producing biofilm were divided into three groups: 1 (2,5%) had strong biofilm formation, 4(10%) were moderate, and 26(65 %) were weak. The phenotypic detection of the efflux pumps was observed in 100% of the bacterial isolates at a concentration of 0.5 mg/l of ethidium bromide(ETBR). The prevalence of the TetA and MdfA efflux pump genes was 72.5% for each. The gel electrophoresis showed that the molecular weight of TetA and MdfA genes were 131bp and 403bp respectively. Keywords: Efflux pumps, Urinary Tract, Infection, Parasites, E-coli.