Detection of vanA and vanB genes Among Vancomycin Resistant Staphylococcus aureus Isolated from Clinical Samples in Baghdad Hospitals

Abstract

Staphylococcus aureus is an opportunistic pathogen. It is most common in skin and soft tissue. This microbe can cause more diseases as a burn inflammation and tonsillitis through the production of virulence factors. In this study, one hundred and fifty (150) samples were collected from patients with inflammation from different clinical sources and different age groups during the period from December 2020 to the end of April 2021.from main hospitals in Baghdad. All isolates were diagnosed based on microscopic examinations and morphological characteristics using Mannitol salt agar, Blood agar in addition to biochemical tests.The diagnosis was confirmed through Vitek system and API staph kit. Antibiotic susceptibility testing was performed on all identified isolates, and the findings revealed that 12 isolates VRSA.DNA was extracted from bacterial isolates and sepreated by electrophoresis to measure DNA purity and integrity. Molecular diagnosis of bacteria was done using a polymerase chain reaction based on the 16SrRNA gene and the results were (100%) as S. aureus. In addition the individual interactions polymerized were used to determine the vancomycin resistance genes. It was found that all isolates were vancomycin resistance through the presence of the van A gene, while the results of the presence of genes van B were (66.6%).