Virulence genes distributed among Staphylococcus aureus causing wound infections and their correlation to antibiotic resistance

Asia Helmi Rasmi; Eman Farouk Ahmed; Abdou Mohammed Abdullah Darwish; Gamal Fadl Mahmoud Gad

doi:10.1186/s12879-022-07624-8

Virulence genes distributed among Staphylococcus aureus causing wound infections and their correlation to antibiotic resistance

BMC Infect Dis. 2022 Jul 28;22(1):652. doi: 10.1186/s12879-022-07624-8.

Authors

Asia Helmi Rasmi¹, Eman Farouk Ahmed², Abdou Mohammed Abdullah Darwish³, Gamal Fadl Mahmoud Gad⁴

Affiliations

¹ Microbiology and Immunology Department, Faculty of Pharmacy, Deraya University, Minia, Egypt.
² Microbiology and Immunology Department, Faculty of Pharmacy, Sohag University, Sohag, Egypt. eman.farouk@pharm.sohag.edu.eg.
³ Plastic and Reconstructive Surgery Department, Faculty of Medicine, Minia University, Minia, Egypt.
⁴ Microbiology and Immunology Department, Faculty of Pharmacy, Minia University, Minia, Egypt.

Abstract

Background: Staphylococcus aureus causes many human infections, including wound infections, and its pathogenicity is mainly influenced by several virulence factors.

Aim: This study aimed to detect virulence genes (hla, sea, icaA, and fnbA) in S. aureus isolated from different wound infections among Egyptian patients admitted to Minia University Hospital. This study also aimed to investigate the prevalence of these genes in methicillin-resistant S. aureus (MRSA), methicillin-susceptible S. aureus (MSSA), and vancomycin-resistant S. aureus isolates and the resistance and sensitivity to different antibiotic classes.

Methods: A cross-sectional study was carried out from November 2019 to September 2021. Standard biochemical and microbiological tests revealed 59 S. aureus isolates. The Kirby-Bauer disc diffusion method was used to determine antibiotic susceptibility. DNA was extracted using a DNA extraction kit, and polymerase chain reaction was used to amplify all genes.

Results: A total of 59 S. aureus isolates were detected from 51 wound samples. MRSA isolates accounted for 91.5%, whereas MSSA isolates accounted for 8.5%. The multidrug resistance (MDR) percentage in S. aureus isolates was 54.2%. S. aureus showed high sensitivity pattern against vancomycin, linezolid, and chloramphenicol. However, a high resistance pattern was observed against oxacillin and piperacillin. sea was the most predominant gene (72.9%), followed by icaA (49.2%), hla (37.3%), and fnbA (13.6%). sea was the commonest virulence gene among MRSA isolates (72.2%), and a significant difference in the distribution of icaA was found. However, sea and icaA were the commonest genes among MSSA isolates (79.9%). The highest distribution of sea was found among ciprofloxacin-resistant isolates (95.2%).

Conclusion: The incidence of infections caused by MDR S. aureus significantly increased with MRSA prevalence. sea is the most predominant virulence factor among antibiotic-resistant strains with a significant correlation to piperacillin, gentamicin, and levofloxacin.

Keywords: Antibiotic resistance; S. aureus; Virulence genes; Wound infections.

MeSH terms

Anti-Bacterial Agents / pharmacology
Cross-Sectional Studies
Drug Resistance, Microbial
Humans
Methicillin-Resistant Staphylococcus aureus*
Microbial Sensitivity Tests
Piperacillin
Staphylococcal Infections* / epidemiology
Staphylococcal Infections* / microbiology
Staphylococcus aureus
Virulence / genetics
Virulence Factors / genetics
Wound Infection* / epidemiology

Substances

Anti-Bacterial Agents
Virulence Factors
Piperacillin