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Jones originally established the criteria for the diagnosis of rheumatic fever: major criteria are carditis, migratory polyarthritis, Sydenham's chorea, erythema marginatum and subcutaneous nodules. Minor criteria include fever, arthralgias and abnormal laboratory findings (elevated ESR, elevated C-reactive protein, or prolonged PR interval on an ECG). To establish the diagnosis of acute rheumatic fever, two major or one major and two minor criteria must be accompanied by evidence of what?
What is an antecedent group A streptococcal infection, e.g. a positive culture or raised or rising antistreptolysin O or antideoxyribonuclease B titer