Case Definition of Streptococcal Toxic-Shock Syndrome (Streptococcal TSS) and Necrotizing Fasciitis

I. Streptococcal TSS

A. Isolation of group A Streptococcus

1. From a sterile site

2. From a nonsterile body site

B. Clinical signs of severity

1. Hypotension

2. Clinical and laboratory abnormalities (requires two or more of the following):

a) Renal impairment

b) Coagulopathy

c) Liver abnormalities

d) Acute respiratory distress syndrome

e) Extensive tissue necrosis, i.e., necrotizing fasciitis

f) Erythematous rash

Definite Case = A1 + B (1+2)

Probable Case = A2 + B (1+2)

II. Necrotizing fasciitis

A. Definite case

1. Necrosis of soft tissues with involvement of the fascia

PLUS

2. Serious systemic disease, including one or more of the following:

a) Death

b) Shock (systolic blood pressure <90 mmHg).

c) Disseminated intravascular coagulopathy

d) Failure of organ systems

a. respiratory failure

b. liver failure

c. renal failure

3. Isolation of group A Streptococcus from a normally sterile body site

B. Suspected case

• 1+2 and serologic confirmation of group A streptococcal infection by a 4-fold rise against:

1. 1. streptolysin O
   2. DNase B

• 1+2 and histologic confirmation:

1. 1. Gram-positive cocci in a necrotic soft tissue infection

*Streptococcal toxic-shock syndrome (streptococcal TSS) is defined as any group A streptococcal infection associated with the early onset of shock and organ failure.