New diagnostic criteria of acute rheumatic fever: prevalence of silent carditis in a pediatric population

Acute rheumatic fever and its sequel, chronic rheumatic heart disease, are important global health issues with an annual incidence of about 500.000 new cases and a prevalence of 34 million people worldwide affected by rheumatic heart disease. During the 20th century the incidence of ARF and the prevalence declined substantially in Europe, North America, and developed nations in other geographic locations. In Italy the incidence is about 4,1:100.000. Acute rheumatic fever is a systemic inflammatory response to group A streptococcal infection, which typically affects children and occurs two or three weeks after a throat infection. Although arthritis is the most common sign, carditis which commonly affects the mitral and aortic valves, is the most specific and severe one, for the eventual risk of chronic rheumatic cardiopathy. Other less common clinical features include chorea, rash (erythema marginatum), and subcutaneous nodules. Diagnosis requires demonstration of the presence of major and minor criteria and laboratory evidence of a recent streptococcal throat infection. In the 1992 AHA revised Jones criteria statement, the diagnosis of carditis was clinical, based on the auscultation of typical murmurs that indicate mitral or aortic valve regurgitation. The Australian and New Zealand Diagnostic Criteria, published on Circulation in 2015, extend the 1992 Jones criteria for acute rheumatic fever by including echocardiographic evidence of silent carditis and a wider spectrum of joint manifestations as major criteria. Subclinical carditis is characterised by the absence of classic auscultatory findings of valvular dysfunction and the by the echocardiographic evidence of mitral or aortic valvulitis.