PVL-associated Staphylococcus aureus infections

PVL-associated Staphylococcus
aureus infections
Infection Control Nurses
December 2009

Introduction
• What is PVL-Staph?
• Why is it important?
• How do we spot it?
• What do we do about it?

History of PVL
• Discovered by Van de Velde in 1894 - ability to
destroy leucocytes
• Named after Sir Philip Noel Panton and Francis
Valentine when they associated this with soft
tissue infections in 1932
• PVL has been seen in the UK since the 1950s
and 60s

What is PVL-Staph?
• Strains of Staphylococcus aureus
producing the toxin Panton Valentine
Leukocidin.
• PVL is a toxin which destroys WBCs
• Can be MSSA or MRSA, but to date,
most PVL-SA in UK have been MSSA
• Less than 2% of S. aureus in England
carry the genetic encoding for PVL
• Usually community-acquired, although
has spread in hospital setting

Clinical significance
• PVL Infections remain uncommon in the UK
• To date, MOST are sensitive to a range of
antibiotics.
• The risk to the UK general public is small,
but the HPA agency is actively raising
awareness of this infection and monitoring
trends - Why?
-Horizon Scanning-

Epidemiology
• Patients often young, previously well
• Majority of PVL-SA cause mild skin and
soft tissue infections
• Rarely, it causes pneumonia, septic
arthritis or bacteraemia in otherwise
healthy young people
• 224 cases of PVL- S. aureus identified in
England in 2005 (117 MRSA), 496 in 2006
(159 MRSA). 62% were MSSA.
• two recent outbreaks in healthcare settings
• 7 deaths in England & Wales in past 2
years

Internationally
• A major problem has emerged with
CA PVL producing MRSA in North
America, the USA300 clone, which is
now spreading within their healthcare
system

HA-MRSA
VS
CA-PVL Staph
1. Elderly, debilitated,
critically/chronically ill patients
2. Infections - wounds, devices,
bacteraemia
3. Transmission - within hosp
setting, less in household
contacts
4. Diagnosis - in-patient setting
5. PMH - Prev colonisation,
recent surgery, adm to
hosp/NH, antibiotics, renal
dialysis, indwelling catheter,
skin ulcers, DM
6. Virulence - PVL neg,
community spread minimal
7. Limited antibiotic agents
1. Patient often young, healthy,
students, athletes, children,
military personnel
2. Infection - skin, cellulitis,
abscesses, necrotising fasciitis,
Pneumonia
3. Community aquired, spreads in
close contacts in family, sports,
via pets too!!!
4. Diagnosis - minor ssti opd,
serious inf in- patient
5. No PMH
6. Virulence - PVL positive, ready
spread in community,
7. More antibiotic susceptibilities

Risk Factors
• Compromised skin integrity
• Skin to skin contact
• Sharing of contaminated items like towels
• CDC - 5 Cs - Contaminated items
Close contact
Crowding
Cleanliness
Cuts
High risk settings - households, gym, military training
camps, prisons, close contact sports

Disease associations
Local
• Skin/soft tissue infection (cellulitis,
abscesses, boils, carbuncles)
Invasive
• Necrotising pneumonia preceded by a
"flu-like” illness
• Bacteraemia
• Necrotising fasciitis
• Osteomyelitis & septic arthritis

Cavitation
Surgical emphysema
Consolidation

Skin and Soft Tissue
Infections

What do we do about it?
• Clinical management
• Infection control

Clinical Management
Skin and soft tissue infections
•Minor SSTIs do not need antibiotic treatment unless
immunocompromised,
Incision and drainage is the optimal management for abscesses.
•Moderate SSTIs including cellulitis and larger abscesses should be
treated with oral anti-staphylococcal antibiotics, and drainage.
•If there is systemic involvement suggestive of toxic shock or
pyomyositis, use empirical parenteral antibiotics for MRSA with
immunoglobulin
General care
Lesions should be covered, personal hygiene emphasised (avoid sharing towels,
bath water etc.), and patients advised to return if the lesions do not resolve or
there is clinical deterioration.

Clinical Management of patient with
suspected PVL-related pneumonia
CAP hospitalised
– treat with local hospital
severe CAP regimen – cefotaxime/
co-amoxiclav and clarithromycin
Clinical suspicion of
PVL–S. aureus pneumonia
Admit to ICU
Obtain cultures:
(isolation and masks to be worn
if exposed to respiratory secretions)
- Bronchoalveolar lavage
Protected specimen brush
Tracheal aspirate or sputum
Start empiric antibiotics covering MRSA
- linezolid , clindamycin ,- if
deteriorating , rifampicin

Infection Control

Decolonisation- Community
•Topical decolonisation should be offered to primary
cases. Repeated screening is not recommended unless
the patient is particularly vulnerable to infection, poses
a special risk to others (e.g. a healthcare worker) or
spread of infection is continuing in close contacts.
• Close household contacts of a patient diagnosed with
necrotising pneumonia likely to be caused by PVL-SA
should be offered a five-day topical decolonization
regimen

Infection Prevention and Control
in Hospital
“Hospitals should have policies and
procedures which deal with MRSA and these
are generally appropriate for the control of
PVL-SA.”
SSTIs - These precautions include:
•isolation in a single room
•use of PPE (plastic apron and gloves)
• meticulous hand hygiene,
•environmental cleaning with Actichlor plus.

Infection Prevention and Control
in Hospital
Necrotising pneumonia
Transmission of PVL-SA to staff has occurred following
contact with respiratory secretions (intubation where PPE
was not worn)
Healthcare workers (HCWs) should:
• wear PPE, (face and eye protection) during intubation and
respiratory care
•be screened by occupational health, three to seven days
after any respiratory exposure when not protected by PPE
•report to a physician if symptoms of infection present after
contact with confirmed case

Screening other Patients and Staff
•Should be performed on a risk assessment
basis
•Positive individuals should receive
decolonisation

On a more positive note:
The outcome of a similar case at Wythenshaw
Hospital in Dec 2007
• ECMO in Leicester for 5 days
• Transferred back to Wythenshawe Hospital 28 th Jan 08
• Weaned off ventilator after 32 days
• Discharged to ward 12 th Feb
• Discharged home with baby 22 nd Feb (baby repeatedly
negative on screening)
• Reviewed in clinic 14 th April – well, CXR clear!

Success depended upon:
• Awareness / clinical suspicion
• Early laboratory detection
Microscopy
Culture
Typing
• Appropriate clinical management
• Screening, decolonisation and infection control

Any
Questions?