Clinical features of necrotizing fasciitis:
(1) necrosis of soft tissue with involvement of the fascia
(2) serious systemic infection, with 1 or more of the following
(2a) death
(2b) shock (systolic blood pressure < 90 mm Hg)
(2c) disseminated intravascular coagulopathy (DIC)
(2d) one or more organ system failures (respiratory, hepatic, renal)
Evidence for streptococcus involvement:
(1) isolation of group A Streptococcus from a normally sterile body site
(2) 4-fold rise in antibodies to streptolysin O and DNAase B
(3) Gram-positive cocci in chains within the necrotic soft tissue
Criteria for Diagnosis
Definite case: both of the following:
(1) both clinical features
(2) isolation of streptococcus from a normally sterile body site
Suspected case: both of the following:
(1) both clinical features
(2) serologic or Gram-stain evidence of streptococcal infection
where:
• I would think the presence of both a serologic rise in antibodies AND Gram stain evidence would make the infection probable.
• Immunoperoxidase stains could be used to confirm the species on smears even if the organism was not isolated on culture.
