PVL ve S. aureus: An overview

1
PVLve S. aureus An overview

• Angela Kearns
• PHMEG, Birmingham 11th Nov 2008

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Panton-Valentine Leukocidin

• Leukotoxin produced by S. aureus
• 2 exoproteins (LukS LukF)

Can J Infect Dis Med Microbiol 200617 Suppl C
Boyle-Vavra et al, Lab Invest 2007873
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PVL phage mediated

• Carried by 5 different phages
• Few strains susceptible to infection
• 2-10 clinical isolates are PVL
• Community S. aureus (MSSA MRSA)

Gene 2001268195
4
USA300 Major public health
problem
Spread to Europe (UK, Germany, Austria, Denmark,
Holland etc)
58 SSTI in Emergency departments
Serious disease in paediatric patients
Multi-resistant strains
PVL-SA
Nosocomial cases transmission
57 SSI (Patel et al, Alabama)
Moran et al, NEJM 2006355666 Diep et al,
Lancet 2006367731-739
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1st report of CA-MRSA in UK
Stacey et al, Br J Sports Med 199832153

• 5 members affected
• Large abscesses several cm diameter
• Arms, neck, back, face
• Failed to respond to ?-lactams
• Played touring team from South Pacific
• SW Pacific clone of CA-MRSA probably imported

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PVL-SA Yearly trends
1361
1400
1200
PVL-MRSA
1000
PVL-MSSA
800
No. PVL-SA
496
600
224
400
200
0
2005
2006
2007
Year
7
Age groups and gender
250
200
150
Male
No PVL-SA
Female
100
50
0
0-16
17-40
41-60
gt61
Not
known
55
Age (years)
8
PVL-SA Clinical presentation
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PVL-SA Epidemiology risk factors

• Close contacts, sharing personal items, skin
  trauma
• Households
• Sports teams rugby, wrestlers
• Military recruits
• Schools nurseries
• Day-care centres (residential elderly)

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Recurrent infections Household
cluster

• 2 siblings with abscesses ? treated
• Recurring abscesses for gt12 months
• Each episode treated on individual basis
• ? Periorbital cellulitis due to PVL-MRSA
• Lessons learnt
• Treatment of individual alone ineffective
• Look at family history break cycle of
  transmission
• Effective management requires holistic approach
• Review and treat/decolonise entire family
  concurrently

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Summary

• PVL-SA major public health problem in USA
• Modest disease burden in UK rest of Europe
• Highly transmissible esp. in community
• Close contacts e.g. families, social groups
• High attack rate
• Considerable morbidity
• Young, previously healthy individuals
• Key challenge - preventing spread in the
  community

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PVL Management algorithm
Advice - Cover lesion - Practice good hygiene -
Avoid sharing personal items - Avoid work/close
contact sports
Confirmed case
Risk factors - Family history - Social
history Contact tracing - Screen close
contacts? - Treat decolonise?
ID Antibiotics
http//www.hpa.org.uk/PVL-SA_FinalGuidance.pdf
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Burden of PVL-SA disease

• Surveillance-based studies (DH funded)
• - Asymptomatic carriage rate in community
• - Pyogenic SSTIs from AE and Walk-in
  centres
• - Volunteers???

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Concerns

• Awareness timeliness of PVLve results
• ad hoc?
• Copy reports to CCDC/HPUs contact Angela
• Evidence base for guidance
• Role of PVL????
• Impact v. resource-intensive
• Consistency between HPUs (action cards)
• National effort
• Inform revision of national PVL guidance

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When to suspect PVL?

• S. aureus (MSSA/MRSA) from a patient with
• Recurrent/multiple boils/abscess
• Necrotising skin and soft tissue infection
• Necrotising pneumonia
• NOT bacteraemias 4/244 (1.6) PVLve all
  MSSAs
• Susceptibility profiles highly variable
• Reliant on clinical suspicion of PVL-related
  syndrome

Esp if lt40y
JAC 200760402-6