From the Guidelines
Acute Rheumatic Fever (ARF) is an inflammatory disease that develops as a delayed complication of untreated group A streptococcal pharyngitis, typically occurring 2-3 weeks after the initial infection, and its clinical presentation includes a constellation of symptoms such as migratory polyarthritis, carditis, subcutaneous nodules, erythema marginatum, and Sydenham's chorea, as outlined in the revised Jones criteria 1. The pathophysiology of ARF involves molecular mimicry, where antibodies produced against streptococcal antigens cross-react with human tissues due to structural similarities, primarily targeting the heart, joints, skin, and central nervous system 1.
Clinical Presentation
The clinical presentation of ARF can vary, but it often includes:
- Migratory polyarthritis (affecting large joints)
- Carditis (which may manifest as new heart murmurs, pericarditis, or heart failure)
- Subcutaneous nodules
- Erythema marginatum (a distinctive rash with central clearing)
- Sydenham's chorea (involuntary, purposeless movements) Patients often experience fever, malaise, and elevated inflammatory markers, such as ESR ≥60 mm in the first hour and/or CRP ≥3.0 mg/dL, as indicated in the revised Jones criteria 1.
Pathophysiology and Pathology
The autoimmune response in ARF leads to valvular damage, particularly affecting the mitral valve, which can progress to rheumatic heart disease with permanent valve scarring 1. Histologically, Anitschkow bodies (fibrinoid collagen degeneration) and Aschoff nodules (granulomatous lesions) are characteristic findings in cardiac tissue.
Diagnosis
The diagnosis of ARF is based on the revised Jones criteria, which include major and minor manifestations, as well as evidence of preceding group A streptococcal infection 1. The revised Jones criteria provide a framework for diagnosing ARF, including the use of Doppler echocardiography to diagnose cardiac involvement, and are essential for guiding treatment and prevention strategies 1. The criteria outline the major and minor manifestations of ARF, including carditis, arthritis, chorea, erythema marginatum, and subcutaneous nodules, as well as laboratory findings such as elevated ESR and CRP.
Prevention and Treatment
Prevention of ARF focuses on prompt treatment of streptococcal pharyngitis with antibiotics like penicillin, and long-term prophylaxis with monthly benzathine penicillin G injections or daily oral penicillin is essential to prevent recurrence and further cardiac damage 1. Treatment of ARF includes antibiotics to eradicate remaining streptococci, anti-inflammatory agents for symptom relief, and in severe cases, corticosteroids. It is essential to note that the revised Jones criteria provide a framework for diagnosing and managing ARF, and adherence to these criteria can help improve outcomes and reduce the risk of complications 1.
From the Research
Clinical Presentation of Acute Rheumatic Fever (ARF)
- Acute rheumatic fever is an inflammatory sequela of Group A Streptococcal pharyngitis that affects multiple organ systems 2
- The disease can present with various manifestations, including carditis, polyarthritis, and Sydenham's chorea, which are the most common major manifestations of ARF 2
- There can be significant overlap with other disorders such as Lyme disease, serum sickness, drug reactions, and post-Streptococcal reactive arthritis, making diagnosis challenging 2
Pathophysiology and Pathology of ARF
- ARF is an autoimmune disease associated with group A β-hemolytic streptococcal infection, which can lead to the development of carditis, arthritis, chorea, subcutaneous nodules, and erythema marginatum 3
- The disease is a delayed, nonsuppurative, autoimmune phenomenon following pharyngitis, impetigo, or scarlet fever caused by group A β-hemolytic streptococcal (GAS) infection 4
- Rheumatic carditis is a manifestation of ARF that may lead to rheumatic heart disease (RHD) 5
Diagnosis of ARF
- The diagnosis of ARF is based on the presence of documented preceding Group A Streptococcal infection, in addition to the presence of two major manifestations or one major and two minor manifestations of the Jones criteria 2
- The Jones criteria have been modified throughout the years, with the most recent revision in 2015, which considers the risk within a population and offers two separate diagnostic pathways that prioritize specificity among those at low risk and sensitivity among those at moderate/high risk 6
- Echocardiography is now recommended in all patients with suspected or confirmed ARF, and subclinical carditis can fulfill a major criterion for ARF in all populations 6, 3