Related Experiment Video
Updated: May 9, 2025
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
Prevalence and Outcome of Infections Caused by Staphylococcus aureus Strains Harboring the Panton-Valentine
Vrushali H Thakar1, Mahadevan Kumar2, Meera Modak2
1Infectious Diseases, Clinical Microbiology, and Antimicrobial Stewardship Programs (AMSP), Bharati Vidyapeeth's Medical College, Pune, IND.
Background:
Staphylococcus aureus, especially Methicillin-resistant S. aureus (MRSA), is responsible for various hospital-acquired (HA) and community-acquired (CA) infections. Mec A gene responsible for methicillin resistance is encoded in Staphylococcal cassette chromosome gene (SCC). CA-MRSA strains often carry SCC mec IV / SCC mec V and Panton-Valentine leukocidin (PVL) genes. PVL-producing MRSA can cause severe skin or soft tissue infections.
Aim:
This study estimates the prevalence and outcome of infections caused by PVL-producing S. aureus strains in outdoor and indoor patients of a tertiary care hospital in Western Maharashtra, India.
Method:
This cross-sectional study included 274 S. aureus strains isolated from various clinical samples during the study period. Detection of Methicillin resistance was done by the cefoxitin disk method and by automated antimicrobial susceptibility (Vitek 2) method. Multiplex PCR was done for the detection of MecA, SCC type IV, Nuc, and PVL gene using appropriate primers.
Results:
Out of 274 S. aureus strains, 151 (55%) were methicillin resistant. The PVL gene was detected in 187 (70.8%) strains and SCC IV in 116 (43.9%) strains. Mec A was detected in all MRSA strains. Both PVL-producing MRSA (83.4%) and MSSA (78.78) strains were isolated commonly from pus samples. Patients with PVL-producing S. aureus infections required more surgical interventions (18.1%) as compared to those with PVL-negative infections (5.19%) (p-value = 0.006). The PVL gene was associated with SCC IV in 84 (58.7%) strains, while 35 (24.4%) PVL-positive strains were not associated with SCC IV. Few SCC IV and PVL-positive S. aureus strains (17 strains) have produced HA infections.
Conclusion:
The prevalence of the PVL gene is 70.8% in S. aureus. PVL and SCC IV genes are markers of CA infection. MRSA strains harbouring PVL and SCC IV gene producing HA infections is a cause of concern. This suggests infiltration of SCC IV gene producing S. aureus strains in hospital settings. Proper antibiotic stewardship practices, strict aseptic techniques, identification, and treatment of carriers are needed to control the spread of CA-MRSA in hospitals and in the community.
Insights
Panton-Valentine leukocidin (PVL) producing Staphylococcus aureus strains, particularly MRSA, are common in India and linked to severe infections. SCC mec IV and PVL genes are markers for community-acquired infections, necessitating improved hospital infection control.
Area of Science:
- Microbiology
- Infectious Diseases
- Genetics
Background:
- Staphylococcus aureus, particularly Methicillin-resistant S. aureus (MRSA), causes significant hospital-acquired (HA) and community-acquired (CA) infections.
- The Panton-Valentine leukocidin (PVL) gene, often found with SCC mec IV/V in CA-MRSA, contributes to severe skin and soft tissue infections.
Purpose of the Study:
- To determine the prevalence and outcomes of infections caused by PVL-producing S. aureus.
- To analyze the association of PVL and SCC mec IV genes with infection types (HA vs. CA) in a tertiary care hospital in Western Maharashtra, India.
Main Methods:
- A cross-sectional study involving 274 S. aureus isolates from clinical samples.
- Methicillin resistance was confirmed using cefoxitin disk and Vitek 2 methods.
- Multiplex PCR was employed to detect MecA, SCC type IV, Nuc, and PVL genes.
Main Results:
- 151 (55%) of S. aureus strains were methicillin-resistant (MRSA).
- The PVL gene was detected in 70.8% of strains, and SCC IV in 43.9%.
- PVL-producing S. aureus infections led to more surgical interventions (18.1%) compared to PVL-negative infections (5.19%). PVL was associated with SCC IV in 58.7% of strains.
Conclusions:
- PVL gene prevalence is high (70.8%) in S. aureus isolates.
- PVL and SCC IV genes are indicators of community-acquired infections.
- The presence of PVL and SCC IV in MRSA strains causing HA infections is concerning, suggesting their infiltration into hospital settings and the need for enhanced infection control.
