Rheumatic Fever
Normal Heart Anatomy
Rheumatic Fever (RF)
Definition:
Rheumatic fever (RF) is an autoimmune
disease affecting the heart and extra-
cardiac sites (joints, brain, skin and
others)
The incidence of RF has been lowered in
the developed countries but is still high in
poor communities
The disease affects children and young
adults (5-15years)
The disease follows upper respiratory
infection (tonsillitis) with Group A Beta
hemolytic streptococci
Theories of Pathogenesis:
Toxic products of streptococci
Immunologic cross-reactivity between
Streptococcal substances and heart muscle
(heart reactive antibodies)
Sensitized T-lymphocytes may lead to cardiac
injury
JONES' CRITERIA FOR
DIAGNOSIS OF RF:
Major Manifestations Minor Manifestations
Carditis (friction rub, Clinical
murmur, cardiomegaly, Fever
CHF) Arthralgia
Arthritis (migratory History of rheumatic fever
polyarthritis, swollen, red, or rheumatic heart disease
tender) Laboratory
Chorea Acute phase reactants
Subcutaneous nodules (ESR, C-reactive protein,
leukocytosis)
Erythema marginatum
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 myocarditis
2. Rheumatic pericarditis
3. Rheumatic endocarditis
1- Rheumatic myocarditis:
Acute phase: it is characterized by the development of
pathognomonic lesions called Aschoffs 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)
Aschoffs body
Blood vessel
fibrinoid degeneration
Aschoff cells
Chronic phase:
Over years or decades the Aschoff
bodies undergo fibrous scarring
2- Rheumatic Pericarditis:
Acute phase: Aschoff bodies are formed
accompanied by serofibrinous inflammation.
Chronic phase: Fibrosis and adhesions may
occur between the visceral and the parietal
layers of the pericardium
3- Rheumatic Endocarditis:
It affects both mural and valvular endocardium
1. 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
Fusion of commisures
Thick valve leaflet
EXTRACARDIAC LESIONS OF RHEUMATIC FEVER
Joints: Rheumatic arthritis affect the large joints in a fleeting
way i.e 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.
Brain: Rheumatic chorea (rapid involuntary purposeless
movements); it is due to inflammation of the basal ganglia. The
condition is reversible
Skin: Rheumatic subcutaneous nodules occur over bony
prominences and their structure is similar to the Aschoff bodies.
Rheumatic arteritis: affecting the coronaries, renal, mesenteric
and cerebral arteries
Pleurisy and peritonitis: serofibrinous type
PERICARDIAL DISEASES
I. PERICARDITIS
Inflammation of the pericardium
Causes
MI, Staphylococcus, tumor, TB, uremia
II. PERICARDIAL EFFUSION
Serous fluid in pericardial sac
Usual cause: Chronic Heart Failure
III. HEMOPERICARDIUM
Myocardial rupture from MI
Trauma
Bleeding from infection, tumor, etc.
Haemorrhage from aorta
Hemopericardium
