Modified Jones criteria

• Used to diagnose acute rheumatic fever
• Major criteria
  • Polyarthritis: A temporary migrating inflammation of the large joints, usually starting in the legs and migrating upwards.
  • Carditis: Inflammation of the heart muscle (myocarditis) which can manifest as congestive heart failure with shortness of breath, pericarditis with a rub, or a new heart murmur.
  • Subcutaneous nodules: Painless, firm collections of collagen fibers over bones or tendons. They commonly appear on the back of the wrist, the outside elbow, and the front of the knees.
  • Erythema marginatum: A long-lasting reddish rash that begins on the trunk or arms as macules, which spread outward and clear in the middle to form rings, which continue to spread and coalesce with other rings, ultimately taking on a snake-like appearance. This rash typically spares the face and is made worse with heat.
  • Sydenham's chorea (St. Vitus' dance): A characteristic series of involuntary rapid movements of the face and arms. This can occur very late in the disease for at least three months from onset of infection.
• Minor criteria
  • Fever of 38.2–38.9 °C (100.8–102.0 °F)
  • Arthralgia: Joint pain without swelling (Cannot be included if polyarthritis is present as a major symptom)
  • Raised erythrocyte sedimentation rate or C reactive protein
  • Leukocytosis
  • ECG showing features of heart block, such as a prolonged PR interval[31][33] (Cannot be included if carditis is present as a major symptom)
  • Previous episode of rheumatic fever or inactive heart disease
• Interpretation
  • Two of the major criteria
  • One major criterion plus two minor criteria