Relationship between Antibiotic Resistance, Biofilm-Formation and Virulence Factors among Multidrug-Resistant Proteus Mirabilis Isolated From Uti Patients in Wasit Province, Iraq

Abstract

One of the most common bacterial illnesses worldwide is urinary tract infections (UTIs). The pathogenesis of Proteus mirabilis depends on its capacity to express virulence factors, such as adhesion molecules, biofilms, proteases, urease, siderophores, and toxins. This species also causes a variety of infections in the urinary tract, burns, and wounds. They also exhibit resistance to several classes of antibiotics. To characterize Proteus mirabilis isolates from UTI patients phenotypically and genotypically for determinants of antibiotic resistance as well as the existence of virulence genes.  Out of 228 urine specimens collected from a patient with suspected UTIs, 40 (17.5%) Proteus mirabilis isolates were identified. The isolates were first identified as related to culture, microscopic examination, and biochemical tests. DNA was extracted from these 40 isolates, the sample's nucleic acid purity ranged from (1.8-2) while its concentration was between (50 - 360 mg/ul). Whole Proteus mirabilis isolates were examined for their resistance against 15 antibiotics belonging to different classes. Meropenem, Amikacin, Ciprofloxacin, Norfloxacin, and Levofloxacin had the lowest rates of resistance discovered in this study, this may be attributable to the poor usage of these antibiotics in Al-Kut hospitals. Meropenem was in the first place it ‎was the most effective and sensitive drug against Proteus mirabilis ‎isolates in the current study. In a phenotypic analysis of ESBLs, it was discovered that 8 (20.5%) of the clinical isolates of the proteus mirabilis were ESBL produced by confirmatory testing whereas 39 (97.5%) were ESBL producers by screening testing. To detect the formation of biofilm, all isolates of Proteus mirabilis were screened by microtiter plate (MTP) and modified Congo red agar (MCRA) methods. In the MCRA method, the results showed that 38 (95%) were black isolates of Proteus mirabilis strong producer biofilm and 2 (5%) were pink isolates which non-producers biofilm. In the MTP method observed 20(50%) non-producers, 5(12.5%) isolates of Proteus mirabilis produced weak biofilm, 9(22.5%) isolates as moderate biofilm and 6 (15%) isolates strong biofilm. In addition, a molecular study using ureC showed that all isolates possess the ureC gene with a molecular weight of 317bp. luxS gene was also detected by PCR and the results showed that (95%) isolates possess this gene by the appearance of the amplicon with a molecular weight of 283bp. ZapA and pm1 genes are present in all (100%) of isolates, while pet gene are not present in all Proteus mirabilis isolates. mrpA gene was detected in Proteus mirabilis isolates by PCR technique and the results showed that (97.5%) of the isolates possessed the gene. Also, the results of this experiment revealed positive amplification for all isolates (95%) mrpI gene in Proteus mirabilis isolates. The current study has shown the great emergence of biofilm-forming and MDR in Proteus mirabilis isolates and harbours a variety of virulence genes.