Virulence and Antibiogram of Escherichia coli strains isolated from Suspected urinary tract infection patients attending selected hospitals in Zaria, Kaduna State, Nigeria

Abstract

Abstract

Urinary tract infections (UTIs) are infections affecting any part of the urinary system, including the kidneys, ureters, bladder, and urethra. They are the second most common type of infection in humans, with most involving the lower urinary tract. UTIs are caused by both Gram-negative and Gram-positive bacteria, with Escherichia coli (particularly uropathogenic strains, UPEC) being the predominant causative agent. UPEC strains possess a range of virulence factors (VFs) that facilitate attachment, invasion, and damage to host tissues. These VFs include adhesins, toxins, iron acquisition systems, lipopolysaccharides, and capsules, often encoded on Pathogenicity Islands (PAIs). In a study conducted across four hospitals in Zaria, Nigeria, Ahmadu Bello University Medical Centre (Samaru), Muslim Specialist Hospital (Dan Magaji), Gambo Sawaba General Hospital (Zaria), and Major Abdullahi Ibrahim Memorial Hospital (Sabon Gari) a total of 200 urine samples were collected (50 from each hospital). Analysis was conducted at the Department of Microbiology, Ahmadu Bello University, Zaria. Out of the 200 samples, 28 (14.0%) tested positive for E. coli. Antibiotic susceptibility testing revealed that all E. coli isolates were 100% susceptible to imipenem but showed complete (100%) resistance to cefoxitin and amoxicillin. Furthermore, 96.4% (27 out of 28) of the isolates were multidrug-resistant (MDR), while 3.6% were resistant to only two antibiotics. The Multiple Antibiotic Resistance (MAR) index showed that 96.4% of the isolates had values greater than 0.3, indicating a high level of antibiotic resistance among the strains.

Keywords: Urinary tract infections, Escherichia coli, imipenem, multidrug-resistant, Multiple Antibiotic Resistance