Molecular Detection of Panton Valentine Leukocidin Toxin Encoding Gene in Methicillin Resistant Staphylococcus aureus from Clinical Isolates in Hospitals, Khartoum State

Abstract

Staphylococcus aureus is an important pathogen inflicting a variety of diseases affecting human health. Of the several disease-causing toxins released by virulent strains of the pathogen, is Panton Valentine Leukocidin (PVL). This is a descriptive cross-sectional study conducted in the Research Laboratory, Sudan University of Science and Technology in the period from April to September 2012. The aim of this study was to detect PVL toxin encoded gene of Staphylococcus aureus within Methicillin Resistant S. aureus (MRSA) and assess its relation to the type of infection with the organism’s virulence. One hundred and seventy samples were collected from patients presented with clinical signs and symptoms of Staphylococcus aureus infecting different sites. Phenotypic cultural methods were adopted to identify the pathogen. Antibiotic susceptibility testing for methicillin was performed on the identified isolates. The DNA was extracted by phenol-chloroform method. Amplification of the gene coding for PVL was demonstrated using PCR analysis. Out of 170 tested isolates, 89 were methicillin resistant S. aureus (MRSA), 15 methicillin intermediate S. aureus (MISA) and the 66 were Methicillin Sensitive S. aureus (MSSA). The PVL gene was amplified from DNA extracted from 2 (2.2 %) MRSA isolated from patients presented with wound skin infections and 87 (97.8 %) MRSA isolates taken from different infection sites were negative to PVL gene. This study concluded that released PVL toxin by MRSA was probably linked with severe infection of the patients. More sampling and research work are required to determine prevalence and role of the toxin in increasing disease severity among Sudanese patients.