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Acute rheumatic fever (ARF) is a delayed, nonsuppurative sequela of a pharyngeal infection with the group A streptococcus
Rheumatic fever can occur at any age, although most cases occur in children 5 to 15 years of age
The mean incidence of ARF is 19 per 100,000 In the United States and other developed countries, the incidence of ARF is much lower at 2 to 14 cases per
100,000; this is probably due to improved hygienic standards and routine use of antibiotics for acute pharyngitis
Following the initial pharyngitis, a latent period of two to three weeks occurs before the first signs or symptoms of ARF appear
(GAS) tonsillopharyngitis presents with abrupt onset of sore throat, tonsillar exudate, tender cervical adenopathy, and fever, followed by spontaneous resolution within two to five days.
The disease presents with various manifestations that may include
Arthritis Carditis Chorea Subcutaneous nodules Erythema marginatum
EXTRACARDIAC LESIONS OF RHEUMATIC FEVER
• Migratory polyarthritis, involving major joints• Commonly involved joints-knee,ankle,elbow &
wrist
• Occur in 80%,involved joints are exquisitely tender
• Arthritis do not progress to chronic disease
Arthritis
Joints: Rheumatic arthritis affect the
large joints joint inflammation is followed by
joint resolution, then another joint become inflamed followed by resolution and so on.
The affected joint is painful, tender, hot & swollen
• Occur in <5%.• Unique,transient,serpiginous-looking
lesions of 1-2 inches in size• Pale center with red irregular margin• More on trunks & limbs & non-itchy• Often associated with chronic carditis
Erythema Marginatum
Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.
Rheumatic fever: erythema marginatum
Skin: Rheumatic subcutaneous nodules occur over bony prominences and their structure is similar to the Aschoff bodies
• Occur in 10%
• Painless,,palpable nodules
• Mainly over extensor surfaces of joints,spine,scapulae & scalp
• Always associated with severe carditis
Subcutaneous nodules
Brain:
Rheumatic chorea (rapid involuntary purposeless movements); it is due to inflammation of the basal ganglia. The condition is reversible
• Occur in 5-10% of cases
• Mainly in girls of 1-15 yrs age
• Clinical signs- pronator sign, milking sign of hands
Sydenham Chorea
• Manifest as pancarditis(endocarditis, myocarditis and pericarditis),occur in 40-50% of cases
• Carditis is the only manifestation of rheumatic fever that leaves a sequelae & permanent damage to the organ
• Valvulitis occur in acute phase• Chronic phase- fibrosis,calcification & stenosis
of heart valves(fishmouth valves)
Carditis
Laboratory Findings• High ESR• Anemia, leucocytosis• Elevated C-reactive protien• ASO titre >200 Todd units.
(Peak value attained at 3 weeks,then comes down to normal by 6 weeks)
Theories of Pathogenesis:
– Toxic products of streptococci – Immunologic cross-reactivity between
Streptococcal substances and heart muscle (heart reactive antibodies)
JONES' CRITERIA FOR DIAGNOSIS OF RF:
• Major Manifestations– Carditis (friction rub, murmur, cardiomegaly, CHF) – Arthritis (migratory polyarthritis, swollen, red, tender) – Chorea – Subcutaneous nodules – Erythema marginatum
• Minor Manifestations– Clinical
• Fever • Arthralgia • History of rheumatic fever or rheumatic heart disease
– Laboratory • Acute phase reactants (ESR, C-reactive protein, leukocytosis) • Prolonged P-R interval on ECG
PATHOLOGY OF RHEUMATIC FEVER• Cardiac Disease (Rheumatic heart disease)• Extra-Cardiac Disease
RHEUMATIC HEART DISEASE
• Rheumatic heart disease: all the heart layers are affected (pancarditis)
1. Rheumatic myocarditis2. Rheumatic pericarditis3. Rheumatic endocarditis
1- Rheumatic myocarditis:Acute phase: it is characterized by the development of
pathognomonic lesions called Aschoff’s Bodies within the myocardium.
Gross features:• Aschoff bodies are multiple tiny nodules (1-2 mm in
diameter)
Microscopic features:• Aschoff body is a lesion composed of:
– Fibrinoid necrosis ( destroyed fragmented collagen)– Surrounded by lymphocytes and histiocytes &– Aschoff cells (large mononuclear or multinuclear macrophages)
Chronic phase:• Over years or decades the Aschoff bodies
undergo fibrous scarring
2- Rheumatic Pericarditis:
3- Rheumatic Endocarditis:
It affects both mural and valvular endocardium1. Mural Endocardium: • i- Acute phase: Aschoff bodies develop in the
endocardium• ii- Chronic phase: healing results in a white patch
Valvular Endocardium
– Vegetations (thrombi) develop at the lines of contact of the cusps causing friction of the swollen cusps.
Rheumatic Mitral Valve
Small vegetations are formed at injured parts
CHRONIC RHEUMATIC VALVULAR DISEASE
• Mitral & Aortic Valves Pathology:– Thickening of valve leaflet, especially along the lines
of closure – Fusion of commissures – Result is mitral or aortic stenosis, insufficiency, or
both
Rheumatic Mitral Stenosis
Thick valve leaflet
Fusion of commisures
Three major goals of treatment:
Symptomatic relief of acute disease manifestations
Eradication of the group A beta-hemolytic streptococcus (GAS)
Prophylaxis against future GAS infection to prevent recurrent cardiac disease
Oral penicillin V is the agent of choice for treatment of GAS pharyngitis in many clinical settings given its proven efficacy, safety, narrow spectrum, and low cost
Amoxicillin is often used in place of oral penicillin in children, since the taste of the amoxicillin suspension is more palatable than that of penicillin
First-generation cephalosporins are an acceptable alternative to penicillin and amoxicillin in the setting of treatment failure or beta-lactam hypersensitivity
Duration — In general, the conventional duration of oral antibiotic therapy to achieve maximal pharyngeal GAS eradication rates is 10 days
Injections of benzathine penicillin provide bactericidal levels against GAS for 21 to 28 days