Comparison of superantigens and attachment factors genes of Staphylococcus aureus in clinical isolates and nasal colonizers in the same patients. (May 2021)

• Record Type: Journal Article
• Authors: Sharabiani, Hamideh Richi; Sadeghi, Javid; Pirzade, Tahere; Rezaee, Mohammad Ahangarzadeh; Ghotaslou, Reza; Laghousi, Delara; Sefidan, Fateme Yeghane; Kafil, Hossein Samadi; Nikbakht, Mojtaba; Mazraeh, Fariba Naeimi; Hematyar, Yalda
• Is Part Of: Microbial pathogenesis. Volume 154(2021)
• Publication Date: 2021-05
• Subjects: Staphylococcus aureus -- Superantigens -- Clonality -- Rep-PCR; 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.2021.104860
• Languages: English
• ISSNs: 0882-4010

Abstract

Abstract: Background: Staphylococcus aureus ( S. aureus ) is a bacterial pathogen can cause a wide range of nosocomial infections. Nasal colonization by S.aureus plays important role both in the epidemiology and pathogenesis of infection. Objectives: The purpose of this study was to investigate the association of clinical isolates and nasal colonizers of S. aureus in the same patients by molecular methods, and their antibiotic susceptibility pattern. Methods: A total of 181 S. aureus isolates were collected from 100 patients admitted that including 100 clinical isolates and 81 nasal swabs from the same patients (19 cases were found as noncarriers). Superantigens and adhesion genes were identified by PCR. Molecular typing of the isolates was performed by repetitive element polymerase chain reaction (Rep-PCR). Antimicrobial susceptibility pattern of the isolates was conducted by disk diffusion. MIC of the isolates to vancomycin was determined by microbroth dilution. The ability of S. aureus isolates to form biofilm was determined by microtiter plate assay. Results: The most frequent adhesion gene in both clinical isolates and nasal colonizer was clf A with 93% and 76%, respectively. Staphylococcal enterotoxin A (SEA) was the most commonly superantigen (68%) in both nasal colonizers (71.6%) and clinical isolates (65%). The highest resistance rate was to erythromycin (45.3%) with 36% and 56.8% in clinical and nasal colonizer isolates, respectively. All S. aureus isolates were susceptible to linezolid and vancomycin. Multiple drug resistance (MDR) was detected in 36% (n = 65) of the isolates. Biofilm formation was identified in 160 (88.4%) isolates with 87% and 90% in clinical isolates and nasal colonizers, respectively. Repetitive element polymerase chain reaction (Rep-PCR) typing divided 181 S. aureus isolates into six clusters. Twelve isolates from clinical isolates and nasal carriers were closely related. Conclusion: There is a high concordance rate between colonizing and clinical isolates of S. aureus in terms of adhesion factors and superantigen genes. It is suggested that nasal decolonization could be effective in the preventing of S. aureus infections. Highlights: In this study, 100 isolates of Staphylococcus aureus were collected from clinical specimens of hospitalized patients and nasal swab from the noses of the same patients. Eighty one isolates of Staphylococcus aureus were obtained from the noses of the same patients. Antibiotic susceptibility testing and biofilm formation as well as identification of virulence factor genes were performed in 181 isolates. The results showed that there is a close relationship between clinical and nasal colonizing isolates.