Infections caused by CA-MRSA have been associated with the presence of Panton-Valentine leukocidin (PVL) toxin which associated with increased disease severity, ranging from cutaneous infection requiring surgical drainage to severe chronic osteomyelitis and deadly necrotizing pneumonia. Panton-Valentine leukocidin (PVL) is a cytotoxin, one of the β-pore-forming toxins. PVL toxin targets cells of the human immune system like polymorphonuclear neutrophils (PMNs), monocytes, and macrophages forming pores on them that cause cytokine release and cell death by apoptosis or necrosis. The aim of this study is the rapid detection of PVL gene using real time PCR in S. aureus isolates recovered from community acquired S. aureus isolates from  adult and pediatric infections,  and  to describe the prevalence of PVL gene positivity in  community acquired. S. aureus strains. This study was conducted on one hundred and fifty clinical isolates of S. aureus isolates forming three groups (group one fifty community acquired isolates from adult infections, group two: fifty community acquired isolates from pediatric infections and group three:fifty hospital acquired isolates as a control group) isolated from different clinical specimens. All isolates were identified by conventional methods such as morphological identification, gram stain, and catalase test. Identification to species level by slide and tube coagulase, culture on DNase agar and mannitol salt agar. Then genotypic detection of PVL gene by real time polymerase chain reaction (PCR) was done. Regarding community acquired isolates from adults and pediatric infections (88%) were positive for presence of PVL gene by real time PCR while all the control isolates were PVL gene negative, of these community acquired S. aureus isolates (80%) were CA- MRSA while (20%) were CA-MSSA. In the present study regarding different types of infection (100%) of osteomyelitis were PVL gene positive but with no statistical significance. There was high statistical significance between skin and soft tissue infections and PVL gene positivity. There was also high statistical significance between skin soft tissue infection isolates and CA-MRSA. In conclusion, there is high percent of PVL gene positivity among CA-MRSA infections, so its rapid detection is recommended for early adjustment of antibiotic treatment.

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