Phenotypic and genotypic study of biofilm formation in Enterococci isolated from urinary tract infections. (July 2017)

• Record Type: Journal Article
• Authors: Fallah, F.; Yousefi, M.; Pourmand, M.R.; Hashemi, A.; Nazari Alam, A.; Afshar, D.
• Is Part Of: Microbial pathogenesis. Volume 108(2017)
• Page Start: 85
• Page End: 90
• Publication Date: 2017-07
• Subjects: Urinary tract infection -- Enterococci -- Biofilm formation -- Antibiotic resistance; Pathogenic microorganisms -- Periodicals; Pathology, Molecular -- Periodicals; Communicable Diseases -- microbiology -- Periodicals; Communicable Diseases -- parasitology -- Periodicals; Micro-organismes pathogènes -- Périodiques; Pathologie moléculaire -- Périodiques; Electronic journals; 616.9041
• DOI: 10.1016/j.micpath.2017.05.014
• Languages: English
• ISSNs: 0882-4010

Abstract

Abstract: Background: Urinary tract infection (UTI) is one of the most frequent types of nosocomial and community acquired infections in humans. Management of multidrug-resistant Enterococci UTI due to the limited therapeutic options is a great challenge for physicians and clinical microbiologists. The role of bacterial biofilms in recurrent urinary tract infections and antimicrobial resistance has great importance for public health. The aim of this study was to investigate the antibiotic susceptibility pattern as well as the phenotypic and genotypic biofilm formation ability of Enterococci isolates from patients with UTI. Methods: A total of 57 isolates of Enterococci were collected from patients with UTI. Enterococcus species were identified using conventional microbiological methods. The antibiotic susceptibility patterns of the isolates were determined by the Kirby-Bauer disk-diffusion. The Modified Congo red agar (MCRA) and Microtiter plate methods used to assess the ability of biofilm formation. All enterococcal isolates were examined for determination of biofilm-related genes, esp, asa1 and ebpR using PCR method. Results: Of 57 enterococcal isolates, 85.9% were recognized as E. faecalis and 14.1% of them were E. faecium . According to our results, linezolid, chloramphenicol and nitrofurantoin were the most effective agents against Enterococcus species. Overall, 26.5% of E. faecalis and 75% of E. faecium isolates were biofilm producers, respectively. Resistance to some antibiotics including penicillin G, ampicillin, vancomycin, nitrofurantoin and chloramphenicol, and ciprofloxacin was significantly higher among biofilm producers than non-biofilm producers Enterococci . The esp, asa1 and ebpR genes were present in 84.2%, 91.2% and 100% isolates. In this study, there was not a significant relationship between presence of these genes and biofilm formation. Conclusion: Our findings reinforce the role of biofilm formation in resistance to antimicrobial agents. Quinupristin/dalfopristin, tetracycline and rifampin may be used as an effective treatment for UTI caused by biofilm producers Enterococci . Our results suggest that biofilm formation is complex and depends on various factors but not just esp, asa1 and ebpR genes in Enterococcus strains. Highlights: Linezolid, chloramphenicol and nitrofurantoin were the most effective agents against Enterococcus species isolated from UTI. Reinforce the role of biofilm formation in resistance to antimicrobial agents. Quinupristin/dalfopristin, tetracycline and rifampin may be used for treatment of UTI caused by biofilm forming Enterococci . Biofilm formation is complex and depends on various factors but not just esp, asa1 and ebpR genes in Enterococcus strains.