Copy Right: The Authors retain the copyrights of this article, with first publication rights granted to Medsci Publications. License Term: Creative Commons Attribution-Share Alike (CC BY-SA) 4.0 Publisher: Medsci Publications [www.medscipublications.com] ISSN: 2249 4995 Official website: www.njmr.in National Journal of Medical Research | Volume 15 | Issue 02 | April-June 2025 145 Nosocomial E. Coli Isolated from UTI Identified Using DNA Markers Based on PCR and Pathogenic Markers Shler Ali Khorsheed 1 1 Ministry Of Education, Open Educational College, Department of Biology, Kirkuk, Iraq DOI: 10.55489/njmr.150220251087 Corresponding author: Shler Ali Khorsheed (Email: shler-ali@uokirkuk.edu.iq) Date of Submission: 24/01/2025 Date of Acceptance: 14/03/2025 Date of Publication: 01/04/2025 Funding Support: None Declare Conflict of Interest: The authors have declared that no conflicts of interest exist. How to cite this article: Khorsheed SA. Nosocomial E. Coli Isolated from UTI Identified Using DNA Markers Based on PCR and Pathogenic Markers. Natl J Med Res 2025;15(02):145-154. DOI: 10.55489/njmr.150220251087 ABSTRACT Background: Urinary tract infections (UTIs) are among the most common bacte- rial infections, with Escherichia coli (E. coli) being the leading causative agent. The increasing resistance of E. coli to commonly used antibiotics, including β- lactam antibiotics, poses a significant clinical challenge. Understanding antimi- crobial resistance patterns and genetic diversity among E. coli isolates is essen- tial for effective treatment and infection control. This study aimed to determine the prevalence of E. coli in UTI cases, assess its resistance to multiple antibiot- ics, evaluate β-lactamase and extended-spectrum beta-lactamase (ESBL) pro- duction, and analyze genetic diversity using molecular techniques. Materials and Methods: A total of 105 urine samples were collected from UTI patients at Rezali Hospital and General Hospital in Erbil (January–June 2024). Disk diffusion was used for antibiotic susceptibility testing, while MIC values were determined for penicillin and cephalosporin. β-lactamase production was assessed using the iodine titration method, ESBLs were confirmed using a disk proximity test, and RAPD markers were used for genetic diversity. Results: E. coli accounted for 48.51% of UTIs, showing high resistance to tetra- cycline (75.71%) and ceftriaxone (95.14%), and complete resistance to ampicillin and amoxicillin. β-lactamase production was detected in 84.62% of isolates, while 5.77% were ESBL producers. Genetic analysis indicated strain diversity, suggesting multiple nosocomial sources. Conclusion: The study highlights multidrug-resistant E. coli in UTIs, emphasizing the need for continuous surveillance and antibiotic stewardship programs to pre- vent treatment failures. Keyword: E. coli, UTI infection, DNA polymerase chain reaction INTRODUCTION The multiple drug-resistant (MDR) bacteria cause noso- comial infections in the majority of hospitalized pa- tients.[1] Furthermore, individuals infected during hospi- tal stay are the main source of mortality and morbidity, and nosocomial urinary tract infections (UTIs) still ac- count for a large percentage of the overall frequency or incidence of nosocomial infections.[2] Escherichia coli, most commonly associated with human infectious dis- eases, has developed antibiotic resistance, which poses a major challenge to treatment.[3] E. coli causes the ma- jority of UTIs in outpatient and inpatient settings.[4] The first detection of β-lactamase in E. coli occurred prior to penicillin's medical approval.[5] Gram positive and Gram negative bacteria produce the enzyme of β-lactamases, ORIGINAL RESEARCH ARTICLE