Streptococcal Toxic shock syndrome is due to the following virulence factor -

Option 1 M protein: Mediates adherence to epithelial cells, inhibits phagocytosis Option 2 Streptococcal toxic shock syndrome By S. pyogenes (M serotypes 1 or 3)with hyaluronic acid capsule. Caused by SPE (Streptococcal pyrogenic exotoxin) or Erythrogenic toxin. 3 Types : Type A and C - Superantigens. Type A and C bacteriophage coded, B toxin chromosomal mediated. Associated with- Scarlet fever, Necrotizing fasciitis, Streptococcal toxic shock syndrome. Option 3 Streptolysin-O (SL-O):- 1. Oxygen labile ( streptolysin-O ), Heat labile 2. Antistreptolysin-O antibodies (ASO) are raised in most of the streptococcal infections and are used as a standard marker for retrospective diagnosis of streptococcal infections (except in glomerulonephritis and pyoderma; where ASO titer is low). Option 4 Lancefield's grouping (for b haemolytic streptococci):- Based on carbohydrate antigen in cell wall, b haemolytic streptococci are fuher divided into 20 serogroups: Group A to V except I and J.