Streptococcal TSS is due to

Streptococcal pyrogenic toxin (SPE) is also called erythrogenic or Dick or scarlatinal toxin. This toxin was named 'erythrogenic' because its intradermal injection into susceptible individuals produced an erythematous reaction. SPEs are superantigens which are T cell mitogens that induce a massive release of inflammatory cytokines, causing tissue damage, fever and shock. Soft tissue infections with some M types of S.pyogenes may sometimes cause a toxic shock syndrome resembling staphylococcus TSS. Streptococcal TSS and necrotizing fasiculitis occur in persons not immune to the infecting M types. Ref: Textbook of Ananthanarayan and paniker's; 10th Edition; Pg:213, 215.