Virulence genes and antimicrobial resistance pattern in Proteus mirabilis strains isolated from patients attended with urinary infections to Tertiary Hospitals, in Iran

  • Azardokht Tabatabaei
  • Khadijeh Ahmadi
  • Alireza Namazi Shabestari
  • Nastaran Khosravi
  • Ali Badamchi
Keywords: Antibiotic resistance; Proteus mirabilis; biofilm; virulence factors.


Background: Proteus mirabilis is a frequent reason for catheter-associated urinary tract infections (UTIs). The aim of this study was to identify virulence genes and antimicrobial resistance patterns in P. mirabilis strains isolated from patients who
attended a tertiary hospital in Iran.

Methods: In this study, 100 P. mirabilis strains from urine samples were isolated. These isolated strains were identified by biochemical and PCR-based tests, and their antibiotic resistance was profiled through a standard procedure using 14 antibiotics.
PCR assays were used to detect virulence-related genes in P. mirabilis strains. The biofilm formation of each P. mirabilis strain was examined.

Results: Of the 100 P. mirabilis isolates, 16 (16%) were multidrug-resistant. High resistance was observed against cotrimoxazole (97%), nalidixic acid (93%), cefotaxime (77%), and amoxicillin (62%). Sixty of the 100 isolates showed resistance against extended-spectrum cephalosporins. The prevalence rates of the genes related to the virulence factors in this study were mrpH (100%), ucaA (91%), hpmA (94%), zapA (95%), ptaA (100%), ureG (100%), pmfA (100%), fliC (97%), and mrpA (90%) using PCR method. Strong biofilm formation was observed in 20% (5/25) of the strains isolated from
non-catheterized samples and 80% (20/25) of strains isolated from catheterized samples.

Conclusions: Resistance to antibiotics and the prevalence of pathogenicity genes are high in Proteus mirabilis strains iolated from UTIs.

Keywords: Antibiotic resistance; Proteus mirabilis; biofilm; virulence factors.


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eISSN: 1680-6905