Professor and Head, Department of Pediatrics, Kasturba Medical College
Acute Rheumatic fever (ARF) is a non-suppurative complication of Group A Beta hemolytic streptococcus (GAS); its boundaries are indefinite and its differentiation from other diseases is sometimes impossible. The mechanism of the disease is unknown and there is no specific laboratory diagnostic test. The diagnosis must therefore be arbitrary and empirical. Dispute on the criteria of ARF has been the fate of this disease since its first description proposed by T. Duckett Jones, MD, in 1944. Committees of American Heart Association (AHA) and World Health Organization (WHO) subsequently modified, revised and edited these criteria to encompass vexing clinical issues and to improve the specificity (Figure I). The current updated criteria are designed to guide physicians in the diagnosis of initial attack of ARF. They do not measure rheumatic activity, establish the diagnosis of inactive or chronic rheumatic heart disease (RHD), or predict the course or severity of the disease. Criteria do not substitute the wisdom and judgment of the clinician, but guide towards diagnosis, with suggestion to follow carefully all questionable cases and restrict the diagnosis of ARF to illness which meets acceptable criteria.
|Pitfalls in the Major Manifestations:|
Most frequent and benign major manifestation, is almost always migratory large joint involvement, virtually never resulting in residual deformity. Limb pains in young children can be confused with polyarthralgia, and together with an innocent murmur may lead to a wrong diagnosis.
Caution is required in diagnosing carditis as rheumatic in origin when myocarditis/pericarditis incremental diagnostic utility of doppler echocardiography for diagnosing rheumatic carditis.
Chorea (Sydenham's chorea; St. Vitus Dance)
As it is a delayed manifestation, other features of ARF may be absent. Screening of choreic patients with Doppler echocardiography may further increment detection of silent valvulitis.
Erythema marginatum and subcutaneous nodules
Erythema marginatum may be mistaken for cutaneous eruptions secondary to drugs/ viral infections or maybe missed in dark skinned persons. They are never seen as an isolated major manifestation and are almost always associated with carditis. Subcutaneous nodules being non-tender may not be noticed unless specifically looked for by the clinician.
|Pitfalls in the Minor Manifestations:|
Fever is generally present early in the course of untreated ARF and maybe absent or not documented in many cases.
Polyarthralgia is a vexing problem if elevated Antistreptolysin O (ASO) is positive and ESR is mildly elevated.
|Pitfalls in Laboratory Criteria:|
Erythrocyte sedimentation rate (ESR); C Reactive protein (CRP)
Elevation of these acute phase reactants (APR) as a single minor criteria offers objective but non-specific confirmation of inflammation. It is often normal with chorea. Anemia elevates and congestive heart failure reduces ESR but does not affect CRP. Corticosteroids and salicylates decrease APR.
Prolonged P-R interval is a non-specific manifestation unrelated to carditis. It does not correlate with the ultimate development of chronic RHD.
Clinical research in several areas is needed including epidemiological studies and determination of prognostic implication of sub clinical valvular regurgitation. Research on basic pathogenetic mechanisms that result in RF in 'at risk' individuals should continue. Further revisions of the Jones Criteria statement will depend on data generated from these areas of research.
|How to Cite URL :|
|Kamath N.. Available From : http://www.pediatriconcall.com/fordoctor/ Conference_abstracts/report.aspx?reportid=88|