Phenotypic and Genotypic Detection of Staphylococcus Epidermidis Delta Toxin From Neonatal Patients in Isfahan and Tehran University Hospitals Publisher



Havaei SA¹ ; Namvar AE¹ ; Moghim S¹ ; Lari AR² ; Akbari M³ Show Affiliations
Source: Molecular Genetics, Microbiology and Virology Published:2014

Abstract

Staphylococcus epidermidis is one of the most important coagulase-negative staphylococci (CoNS) in the NICU. Various bacterial virulence factors of this opportunistic microorganism such as intercellular protein adhesion, slime layer formation and delta toxin in particular have increased the percentage of true infections. Due to the lack of research on molecular detection of Staphylococcus epidermidis delta toxin and also the unknown percentage of delta toxin in neonate units of the selected university hospitals of Isfahan and Tehran in Iran, we used hld gene as a specific target for detection of mentioned toxin in the present study. Clinical invasive strains of Staphylococcus epidermidis were isolated from different sources of infections including blood culture, blood and urinary catheters, wounds and etc. Using phenotypic method 67.5% of all strains were found to have the ability to produce delta toxin in vitro while 87.5% were found to harbor hld gene in molecular test. Conversely antimicrobial susceptibility test was performed by disc diffusion method on Mueller-Hinton agar. No resistance to vancomycin was observed whereas resistance to cefoxitin (75%), oxacillin (65%) and gentamicin (62.5%) was noticeable. © 2014 Allerton Press, Inc.