- A postinfectious inflammatory disease caused by rheumatogenic strains of group A β-hemolytic Streptococcus (GABHS)
- Acute rheumatic fever (ARF) results in a wide range of disease, from mild joint involvement to chronic carditis.
- The most significant socioeconomic impact is caused by its most severe form, rheumatic heart disease (RHD). Although rarely fatal in the acute phase, chronic RHD may result in significant disability and shortened lifespan.
- Occurs usually following pharyngitis with rheumatogenic GABHS strains
- GABHS strains causing skin infections have also been associated with ARF in the developing world.
- Initial episode of ARF/RHD seen primarily in patients 5 to 15 years of age; chronic RHD presents in young adults.
- Incidence of 2 to 14 per 100,000 per year in the United States.
- Global annual incidence of 350,000 in children
- 350,000 deaths annually
- Historically, untreated GABHS infection results in ARF in 0.1–0.3% of cases, with attack rates as high as 3% in endemic areas.
- 40% of patients with RHD did not have recognized ARF.
- Profound decrease in incidence in developed world due to increased use of antibiotics, improved living conditions, nutrition, and changing virulence patterns of GABHS strains
- 33 to 34 million people are affected by RHD worldwide; probable underestimation due to poor data collection in some parts of developing world
- RHD accounts for 25–40% of all cardiac disease worldwide.
- RHD accounts for greatest cardiovascular-related loss of disability-adjusted life years.
Strongly associated with overcrowding and socioeconomic deprivation
No specific genetic risk factor identified, although numerous studies have demonstrated polygenic association of ARF with specific human leukocyte antigen (HLA) alleles; concordance risk in twins.
- Primary prevention
- Interventions to address poverty, crowding, and housing challenges
- Appropriate and early treatment of GABHS pharyngitis
- Treatment of ARF
- Antibiotics: full course of penicillin or equivalent to eradicate active infection; does not alter course of carditis
- Anti-inflammatory: High-dose aspirin is standard; steroids may help for severe carditis but remain controversial.
- Cardiac support: aggressive support of cardiac function and use of systemic afterload reduction for severe disease
- Surgical valvuloplasty or valve replacement may be necessary in severe cases.
- Bed rest: controversial; recommended at times for severe cases
- Surveillance screening for RHD
- 10 times more RHD can be detected by echocardiography than auscultation.
- Echocardiographic screening with handheld devices, including by nonexperts needs to be studied further before adoption.
- Secondary prevention of recurrence
- Ideally administered as penicillin G benzathine as a monthly IM injection, but oral daily penicillin or erythromycin is acceptable in areas of low prevalence
- Duration is based on clinical presentation and degree of cardiac involvement:
- ARF without cardiac involvement: 5 years or until age 21 years, whichever is longer
- ARF with mild or resolved carditis: 10 years or until age 21 years, whichever is longer
- ARF with RHD: 10 years or until age 40 years, whichever is longer; consider lifelong if high risk.
- GABHS triggers a complex inflammatory host response, affecting the heart, joints, brain, blood vessels, and subcutaneous tissue.
- Classic example of molecular mimicry, in which the host produces antibodies to certain GABHS antigens, which are similar in structure to host proteins such as vimentin (valve protein), myosin, resulting in cross-reactive autoimmune tissue damage
- Aschoff nodules are proliferative lesions noted in the myocardium that may persist for months to years after initiation of disease.
- New recognition of disease causing serotypes other than classical “rheumatogenic strains”
Immune-mediated inflammatory reaction to specific rheumatogenic strains of GABHS
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