Aras Part Medical International Press International Journal of Medical Parasitology and Epidemiology Sciences 2766-6492 7 2 2026 06 29 Detection of β-Lactamase and Virulence-Associated Genes in Multidrug-Resistant Proteus Mirabilis Isolates from Urinary Tract Infections 67 76 10.34172/ijmpes.6263 EN Aqeel Shanan Omran https://orcid.org/0009-0009-3709-3734 Journal Article 10.34172/ijmpes.6263 2026 04 15 2026 06 11 Introduction: P. mirabilis is becoming an opportunistic pathogen of significant importance among those causing UTIs. Increased incidence of P. mirabilis strains resistant to multiple antibiotics and exhibiting virulence factors has been reported. Resistance to beta-lactam antibiotics due to the development of beta-lactamase enzymes has created numerous difficulties for UTI treatment. The current research aimed to investigate the antimicrobial sensitivity, phenotypic production of ESBLs, biofilm-forming capacity, hemolytic capability, and molecular identification of resistance- and virulence-associated genes in P. mirabilis strains isolated from UTI cases in Al-Diwaniyah, Iraq. Methods: Urine samples from UTI patients were collected and cultured to isolate the test bacteria. The bacteria were detected using traditional microbiological and biochemical analysis and the VITEK 2 system. Susceptibility tests to different antimicrobials were performed utilizing the Kirby-Bauer disc diffusion technique. The double-disc synergy test accomplished phenotypic determination of ESBL. Biofilm-forming capability and hemolytic activity were analyzed using the Congo Red Agar and Blood Agar media, respectively. Gene detection was performed by PCR targeting the 16S rRNA, blaTEM, blaSHV, blaCTX-M-8, blaCTX-M-9, hpmA, and luxS genes. Results: Multi-drug resistance was detected in P. mirabilis strains against ampicillin, erythromycin, clindamycin, clarithromycin, penicillin G, cephalothin, and cefaclor. Many of the isolates produced ESBLs, formed biofilms, and exhibited hemolytic activity. The PCR results showed the presence of the blaTEM (516 bp), blaSHV (1000 bp), blaCTX-M-8, blaCTX-M-9, hpmA, and luxS genes. Conclusion: The simultaneous presence of multidrug resistance and virulence factors in clinical isolates of P. mirabilis underscores the need for continuous monitoring and preventive measures to prevent the spread of resistance.