Transcript PVL - drchrismjones

P.V.L.
Christopher Jones
2011
What is it NOT?
• MRSA
• ESBL
• Any other form of antibiotic resistant
bacterium
• (Although antibiotic resistance might be
incidentally present)
What is it then?
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Panton-Valentine Leukocidin
A virulence enhancing cytotoxin
Discovered in 1894
Named after Sir Philip Noel Panton and
Francis Valentine after they associated it
with soft tissue infections in 1932
Where does it come from?
• Arises as a result of bacteriophage
infection of Staph Aureus (MSSA or
MRSA)
• Genetic material integrated into the
bacterial chromosome
What does it do?
• Causes a release of two proteins (LukSPV & Lukf-PV) from the bacterium
• These join together to form a protein ring
in the membrane of host cells (esp white blood cells)
with a central pore
• Result in leakage of intracellular contents
and formation of superantigens,
undermining targeted immune response
Why is it significant?
(medically)
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Aggressive Staph Aureus infection
Causes severe local tissue necrosis
Necrotising fasciitis
Necrotising Pneumonia.....
Necrotising Pneumonia
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PVL pneumonia
Necrotising vasculitis
Pulmonary haemorrhage
Pulmonary infarction
Leukopenia (from destruction of WBCs)
Shock
75% mortality if not diagnosed early and
treated aggressively.
Why is it significant?
(epidemiologically)
• Linked to:
– Overcrowding
– Communal residences
– Contact sports
– Skin damage
• Local Royal Marine base
Management
• Consider possibility of diagnosis (especially
in infection in healthy adults)
• Appropriate infection control measures
• Microbiology – culture and sensitivity
• “Virology” – polymerase chain reaction
testing
• Antimicrobials
• MSSA: flucloxacillin, erythromycin, clindamycin
• MRSA: clindamycin, rifampicin and doxycycline or
fusidic acid or trimethoprim
Infection Control
• Remember:
– The microbiologists are your friends
– The infection control nurses are not always
your enemies
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