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


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

a) streptolysin O

b) DNase B

2. 1+2 and histologic confirmation:

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.


  1. Stevens DL. Streptococcal toxic-shock syndrome: spectrum of disease, pathogenesis, and new concepts in treatment. Emerg Infect Dis. 1995 Jul-Sep;1(3):69-78. [Medline]

  2. Stevens DL. The toxic shock syndromes. Infect Dis Clin North Am. 1996 Dec;10(4):727-46. [Medline]


Created: February 23, 2006
Last Modified: 02-23-2006