Invasive GAS Flashcards
What are the risk factors for invasive GAS?
8
HIV Cancer Heart disease Diabetes Lung disease Alcohol abuse IVDU Pregnancy VZV - especially with secondary cases in day care
What is the general incidence of invasive GAS?
What is the incidence of invasive GAS in household contacts?
- 7/100000
0. 6-2.9/1000 (20-100x higher)
Is GAS reportable?
Invasive GAS is reportable in all provinces in Canada, then reported nationally once confirmed.
How do you define invasive GAS?
A confirmed case requires isolation of GAS from a sterile site.
One of the following:
- TSS
- soft tissue necrosis (NF, myosotis, gangrene)
- meningitis (7% of invasive disease)
How do you define TSS?
Hypotension and two of the following:
- coagulopathy
- renal impairment
- liver dysfunction
- ARDS
- maculopapular rash +/- desquamation
Is GAS pneumonia an invasive disease?
Only if GAS is isolated from a sterile site with no other apparent cause.
If GAS is isolated on BAL, it does not meet criteria for invasive disease.
How do you define a close contact?
Household contact - spent 4 hours per day for the last seven days or 20 hours per week
Non household - share the same bed or had sexual relations
Mucous membrane contact
Shared needles
Long term car facility
Selected hospital contacts and daycare contacts
Who gets offered chemo prophylaxis?
Close contacts
Contact 7 days before symptoms up to 24 hours of antibiotic therapy
What do you advise close contacts?
Seek medical attention if febrile up to thirty says after diagnosis of index case
Do you give chemo prophylaxis to all daycare kids and staff?
Only if it is a home or family day care. Not for institutional daycare unless exceptional circumstances (a couple kids with invasive GAS)
What are the options for chemoprophylaxis?
- 1st generation cephalosporin - cephalexin
2. 2nd generation cephalosporin - cefuroxime or cefixime
Given GAS melts at the site of penicillin, can you use a standard penicillin for chemoprophylaxis?
Yes, but it is less effective for eradication of colonization
What chemoprophylaxis can you use if beta lactam allergic?
Macrolide, although there are Macrolide resistance GAS so you need good follow up
Clinidamycin.
Do you need to prove cure for either index case or contact?
No.
How do you treat invasive GAS?
GAS TSS?
Penicillin
Clinidamycin - the addition of Clinidamycin is more effective than penicillin alone
TSS - IVIG
