Streptococcus pyogenes

Laboratory identification

• Gram positive cocci

  • arranged in pairs or chains

• Catalase negative

  • do not produce bubbles of gas when hydrogen peroxide added

• beta-haemolytic (complete haemolysis)

• Lancefield  group A (with S. anginosus)

Features

• capsule preventing phagocytosis

• pyrogenic exotoxins

• streptolysins A/O

• Streptokinase

Diseases

• Pharyngitis

• Scarlet Fever

• Pyoderma / Impetigo

• Erysipelas

• Cellulitis

• Necrotising fasciitis

• Bacteraemia /Septicaemia

• Rheumatic fever

• Acute glomerular nephritis

Antibiotics

• Penicillin (very sensitive)

• Erythromycin

• Cephalosporin

• Flucloxacillin

• Vancomycin