Document Type : Original Article

Author

Abstract

Pink eye or conjunctivitis remains one of the most widespread eye infections where
Staphylococcus aureus which is both virulent and antibiotic-resistant stands among several
infecting pathogens as a Gram-positive bacterium. This study aimed to characterize
Staphylococcus aureus in conjunctivitis, focusing on antimicrobial susceptibility Patterns, efflux
pumps and virulence genes. The researchers obtained 150 sample collections from patients
experiencing symptoms of conjunctivitis at From Al-Nasiriyah Teaching Hospital along with AlHaboubi General Hospital in Ophthalmology Consultant at Dhi-Qar Governorate in Iraq
throughout August to December 2024. These samples received culture on blood, chocolate, and
MacConkey agar media. Of the isolates, 34 (40%) were typed as Staphylococcus aureus by the
Vitek2 compact system. Antibiotic susceptibility testing revealed resistance in some of the isolates,
and further assessment of efflux pump activity was conducted by the ethidium bromide cartwheel
method. Of the 20 resistant isolates, 7 (20.6%) were found to have efflux pump activity. Molecular
analysis by PCR identified the presence of three virulence genes sigB, katG, and clfA in all effluxpositive isolates. The genes perform multiple functions which include stress response together with
oxidative defense and host adhesion mechanisms and specifically contribute to Staphylococcus
aureus pathogenicity of conjunctivitis. The article highlights Staphylococcus aureus's survival and
adaptation through antibiotic resistance and virulence factor mechanisms and producing
difficulties in bacterial conjunctivitis control.

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