Effect of Proteus Mirabilis Biofilm Formation on Antibiotic Resistance in Urinary Tract Infections
Downloads
Introduction & objectives: Proteus mirabilis is a frequent cause of UTIs in women. Its ability to produce biofilms increases the resistance against several antibiotics and makes its treatment even more challenging. The main objectives of this study were to estimate distribution of P. mirabilis in UTI infected female patients, determine the antibiotic resistance patterns, evaluate biofilm formation and explore association between biofilm production and multidrug resistance.
Materials & Methods: In total, 175 urine samples were taken from female patients in Kirkuk hospitals. The isolates were characterized by morphology, biochemical testsand VITEK 2 system. Antibiotics sensitivity profile was determined using the Kirby-Bauer disk diffusion technique for 14 antibiotics. Biofilm production was measured by 96-well microtiter ELISA).
Results: Out of 175 samples, 87 (49.7%) were positive for P. mirabilis. All isolates were confirmed by biochemical tests and VITEK 2. Furthermore, molecular confirmation revealed that all 17 selected isolates (100.0%) carried the 16S rRNA gene, confirming their identity as P. mirabilis. Resistance was highest against ampicillin (78%), cefotaxime (65%), and trimethoprim-sulfamethoxazole (60%), while amikacin (90%) and meropenem (88%) were largely effective. MDR isolates were 36 (41.4%), XDR 12 (13.8%), and EDR 3 (3.4%). Biofilm formation was detected in 75 isolates (86.2%), with 25 strong (28.7%), 30 moderate (34.5%), 20 weak (23%), and 12 non-producers (13.8%). Strong and moderate biofilm producers showed higher MDR/XDR rates (88% and 83%, respectively).
Conclusions: P. false mirabilis is a common isolate in female UTIs in Kirkuk, and biofilm formation dramatically increases drug resistance. These results highlight the need to take account of biofilm-based resistance in clinical treatments.
1. Aziz RAR, Mohameed ES. Characterization of biofilm production in XDR Proteus mirabilis isolated from Baghdad city hospitals. Kufa J Vet Med Sci. 2020;11(2):70-78. doi: 10.36326/kjvs/2020/v11i23297.
2. Ahmed IF, Abbas IM. Detection of some virulence factors and aac(6)Ib resistance gene in clinical Proteus mirabilis isolates. Acad Sci J. 2024;03(03):878B. doi: 10.24237/ASJ.03.03.878B.
3. Flamerz NA, Obid SS, Jasim WM. Study the effect of biofilm production on antibiotic resistance in Proteus mirabilis isolated from clinical samples in Kirkuk City. NTU J Pure Sci. 2023;2(1):339. doi: 10.56286/ntujps.v2i1.339.
4. Owaied H, Jabur S. Antibiotic susceptibility of Proteus mirabilis isolated from clinical samples in Thi-Qar Province. Univ Thi-Qar J Sci. 2022;9(2):901.
5. Abdullah BH, Ismael SS, Qasim NA. Antimicrobial Susceptibility of Proteus mirabilis Isolated from Urinary Tract Infections in Duhok City, Iraq, Using VITEK2 System. Eur J Med Health Res. 2024;2(4):75-79. doi: 10.59324/ejmhr.2024.2(4).09.
6. AL-Dahlaki SM. Biofilm formation by Proteus mirabilis isolated from patients with UTIs in Baqubah City. Acad Sci J. 2025;2(4):865A. doi: 10.24237/ASJ.02.04.865A.
7. Jawad MM, Mohammed AF, Aisha SO. UreC gene detection of Proteus mirabilis isolated and identified from patients with UTIs, Baghdad and Kirkuk general hospitals, Iraq. Microbes Infect Dis. 2025;6(4):6689-6698. doi: 10.21608/mid.2025.373132.2671.
8. Mahmood A, Muthanna HH. Isolation and identification of biofilm-forming Proteus mirabilis with multidrug resistance from different clinical samples. Microbes Infect Dis. 2025;6(4):6738-6745.
9. Mishu NJ, Shamsuzzaman SM, Khaleduzzaman HM, Nabonee MA, Dola NZ, Haque A. Association between biofilm formation and virulence genes expression and antibiotic resistance pattern in Proteus mirabilis. Arch Clin Biomed Res. 2022;6(3):418-434. doi: 10.26502/acbr.50170257.
10. Wasfi R, Hamed SM, Amer MA, Fahmy LI. Proteus mirabilis biofilm: development and therapeutic strategies. Front Cell Infect Microbiol. 2020;10:414. doi: 10.3389/fcimb.2020.00414.
11. Nissanka MC, Dilhari A, Munasinghe JA, et al. Decoding Proteus mirabilis biofilms: expression of virulence genes and association with antibiotic resistance. BMC Microbiol. 2025;25:481. doi: 10.1186/s12866-025-04212-z.
12. Wasfi R, Abd El-Rahman OA, Mansour LE, Hanora AS, Hashem AM, Ashour MS. Antimicrobial activities against biofilm formed by Proteus mirabilis isolates from wound and urinary tract infections. Indian J Med Microbiol. 2012;30(1):76-80. doi: 10.4103/0255-0857.93044.
13. Alqurashi E, Elbanna K, Ahmad I, Abulreesh HH. Antibiotic resistance in Proteus mirabilis: Mechanism, status, and public health significance. J Pure Appl Microbiol. 2022;16(3):1550-1561. doi: 10.22207/JPAM.16.3.12.
14. Lordejani AS, Tajbakhsh E, Khamesipour F, Momtaz H, Shahraki MM. Prevalence, antibiotic resistance, and biofilm formation of Proteus mirabilis. Vet Med Sci. 2025;11(6):e70600. doi: 10.1002/vms3.70600.
15. Atheer A. R., Hasanain K. S. Isolation and Analysis of Nucleotide Sequences of the 16SrRNA Gene of Pseudomonas aeruginosa Isolated from Clinical Samples. Indian Journal of Forensic Medicine & Toxicology, 2021; 15(1): 2193-2198.
16. Cernohorská L, Chvílová E. Proteus mirabilis isolated from urine: resistance to antibiotics and biofilm formation study. Klin Mikrobiol Infekc Lek. 2011;17(3):81-5. [PubMed ID: 21780025].
17. Hassuna NA, Abdelrahim SS, et al. Characterization of antimicrobial resistance among Proteus mirabilis isolates from catheter-associated and non-catheter-associated urinary tract infections in Egypt. BMC Infect Dis. 2025;25:767. doi: 10.1186/s12879-025-11118-8.
18. Hussein EI, Al-Batayneh K, Masadeh MM, Dahadhah FW, Al Zoubi MS, Aljabali AA, et al. Assessment of pathogenic potential, virulent genes profile, and antibiotic susceptibility of Proteus mirabilis from urinary tract infection patients. Int J Microbiol. 2020;2020:1231807. doi: 10.1155/2020/1231807.
19. Mirzaei A, Habibi M, Bouzari S, Asadi Karam MR. Proteus mirabilis isolates from urine and their virulence genes patterns, Tehran, Iran. Infect Drug Resist. 2019;12:3967–3979. doi: 10.2147/IDR.S230303.
20. Serry FM, El-Masry EM, Sadek RA, Girgis MM. Prevalence and antibiotic resistance patterns of Proteus mirabilis isolated from catheter-associated urinary tract infection (Zagazig University study). Zagazig J Pharm Sci. 2014;23(1):34-43. doi: 10.21608/zjps.2014.38178.
21. AL-Dahlaki SM. Biofilm formation by Proteus mirabilis isolated from patients suffering from urinary tract infections in Baqubah City. Acad Sci J. 2024;2(4):148-155. doi: 10.24237/ASJ.02.04.865A.
22. Chakkour M, Hammoud Z, Farhat S, El Roz A, Ezzeddine Z, Ghssein G. Proteus mirabilis: Overview of epidemiology, risk factors, and molecular characterization. Front Microbiol. 2024;15:1383618. doi: 10.3389/fmicb.2024.1383618.
23. Tabatabaei A, et al. Virulence genes and antimicrobial resistance patterns in Proteus mirabilis isolates from UTIs (Iran). PubMed. 2021.
24. Ibrahim AM, et al. Characterization of antimicrobial resistance among Proteus mirabilis isolates from catheter-associated and non-catheter UTIs (Minia, Egypt). BMC Infect Dis. 2025;25:767.
