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Rheumatic Heart Disease Australia

RHD Resouces

Defining risk groups for acute rheumatic fever diagnosis

Current definitions

Rheumatic heart disease awareness (RHD) is increasing across Australia, particularly to southern and eastern areas of the country. It is estimated that this activity and a high level of education around rheumatic fever and RHD are resulting in clinicians outside known high burden RHD areas more frequently considering their populations in relation to acute rheumatic fever (ARF). It is important to correctly diagnose ARF; to over-diagnose could result in years of unnecessary treatment; to under-diagnose could result is the development of unchecked RHD.  

Two risk groups have been defined to help clinicians classify individuals who present with symptoms; high risk, and others. According to the current national guidelines ‘the Australian guideline for prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease (2nd edition)’  (p32), individuals in the high risk category will live in communities with high rates of rheumatic fever in children (>30/100,000) and/or high rates of RHD for all ages (>2/1000). Further, “Aboriginal people living in rural and remote areas are known to be at risk,” and “Aboriginal people in urban settings, Maoris and Pacific Islanders, and potentially immigrants from developing countries, may also be at risk.” All others are assumed to be at lower risk. 

Risk is based primarily on environment. Rheumatic fever is more common in people living in environments where there is poor housing, overcrowding and poverty, however, an Aboriginal or Torres Strait Islander person presenting with symptoms is likely to automatically be placed in the high risk category, particularly when rates of disease in the home environment are not readily available. 

Applying The Australian guideline for prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease (2nd edition) 

Diagnosis of rheumatic fever in Australia requires consideration of one of two sets of criteria, based on the individual’s perceived risk. That is, the likelihood that the presenting illness is rheumatic fever in a given individual. For high risk individuals, the presence of subclinical carditis on echocardiogram, mono-arthritis or polyarthralgia can be used as major manifestations; that is, these symptoms are more powerful when considering a diagnosis.  The American Heart Association guidelines are now aligned to include two levels of risk. 

The diagnosis calculator developed by RHDAustralia  in 2015 provides clinicians with a tool to quickly identify a person suspected to have rheumatic fever based on presenting signs and symptoms. The calculator is being reviewed following feedback from clinicians who find risk group classification of some individuals in outside the top end of Australia less clear. As awareness and surveillance for ARF increases outside the known high burden areas, individuals previously assumed to be at high risk will need further consideration. The calculator will help clinicians determine level of risk so that the clinical manifestations can be more appropriately applied.