invasive GAS infection

Question 1

risk factors for invasive GAS disease

Answer 1

adults with HIV, diabetes, lung disease, alcoholism, injection drug use, post partum,
children pharyngitis and varicella

Question 2

when to report IGAS

Answer 2

if lab confirmatory evidence of GAS in a normally sterile site (with or without evidence of severe invasive disease)

Question 3

what constitutes severe IGAS

Answer 3

1. streptococcal TSS
   - hypotension plus 2 of
   renal impairment, coagulopathy, liver function abnormality, ARDS, generalized erythematous rash (may or may not desquamate later)
2. soft tissue necrosis (NF, myositis, gangrene)
3. meningitis
4. pneumonia (with isolated GAS from pleural fluid or + blood culture) BAL not considered normally sterile site
5. life threatening condition or infection with GAS

Question 4

What is the definition of non severe IGAS

Answer 4

bacteremia, cellulitis, wound infection, lymphadenitis, abscess, septic arthritis, osteomyelitis.

Question 5

clinical presentation of streptococcal NF is often

Answer 5

associated with generalized rash, strawberry tongue, pharyngitis and conjunctivitis

Question 6

recommended empiric antimicrobial therapy for TSS

Answer 6

cloxacillin + clinda (need to cover both staph and strep)

Question 7

empiric therapy for NF

Answer 7

depends on clinical presentation
if associated with chemo, abdominal or pelvic infection, pregnancy complications should treat as polymicrobial and start pip-tazo + clindamycin
if none of those risk factors or contact with waterbourne pathogens can do clindamycin and penicillin

Question 8

why use clindamycin in treatment of severe IGAS?

Answer 8

has inhibition of toxin production in addition to antimicrobial activity.
has been shown to improve outcomes in all empiric and confirmed cases of IGAS.
can discontinue after 72 hours if patient is getting better.

Question 9

what additional treatment can be considered in addition to clindamycin in severe IGAS?

Answer 9

IVIG 1-2 g/kg x 1 dose or 150-500 mg/kg/day over 5-6 days

do this if not responding to initially therapy and patient is still severely ill

Question 10

who should receive prophylaxis with a case of IGAS?

Answer 10

any household contact that spent > 20 hr or 4 hours at at time with the index case
any non household contact that shared a bed with the index case, or had direct contact with the open lesion or mucous membranes
IV drug users who shared needle with index case
selected child care contacts

for child care settings it is recommended for home or family day cares
not recommended for group or institutional day cares unless there has been more than one child affected within 30 days of exposure to index case

Question 11

what is chemoprophylaxis of choice for IGAS?

Answer 11

1. keflex 25-50 mg/kg max 1 g per day div BID-QID x 10 days

can consider clarithro or clinda if allergic to penicillin