12th March 2024

Diagnosis

Diagnosis is primarily clinical, and the Jones criteria are used to facilitate diagnosis of rheumatic fever. This requires the presence of either two major criteria or one major and two minor criteria to be fulfilled in addition to evidence of a recent streptococcal group A infection. The major and minor criteria are defined below:

Major criteria

• Carditis: serial echocardiograms are required for diagnosis and further monitoring.
• Arthritis
• Chorea 
• Erythema Marginatum 
• Subcutaneous nodules  

Minor criteria

• Arthralgia: this is difficult to differentiate from arthritis and cannot be used as a criterion if arthritis is present. 
• First-degree heart block: prolonged PR interval on electrocardiogram. This cannot be used as a criterion if carditis is present.
• Fever: >39 degrees C is typically present in the first few days of illness and can be lower in subsequent weeks
• Raised acute phase reactants: ESR and CRP during the initial weeks. These are not specific for rheumatic fever. 

Recent streptococcal infection

• Evidence of recent streptococcal group A infection is provided by a positive pharyngeal culture or raised streptococcal antibody titre. Anti-streptolysin O titre (ASOT) or DNase B titre are examples of streptococcal antibodies.