• Caused by Staphylococcus aureus
  • Occurs in horses and pigs usually due to wounds
  • Lowgrade persistent infection -> granulomatous lesions
  • Grossly:
    • Hard nodules with fibrous capsule in muscles
    • Contain yellow-brown pus and granules
  • Histologically:
    • Encapsulated granulomatous lesions
    • Central club colonies
    • Staphylococci are present


    • Granulomatous dermatitis caused by nonfilamentous bacteria
    • Usually Staphylococcus aureus
    • Small, yellow granules are formed - sulfur granules
      • Central bacteria surrounded by homogeneous eosinophilic material
  • Filamentous bacteria can also cause granulomas