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) 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 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 affects children and young adults (5-15years) The disease follows upper respiratory infection (tonsillitis) with Group A Beta hemolytic streptococci The disease follows upper respiratory infection (tonsillitis) with Group A Beta hemolytic streptococci

Theories of Pathogenesis: Toxic products of streptococci Toxic products of streptococci Immunologic cross-reactivity between Streptococcal substances and heart muscle (heart reactive antibodies) Immunologic cross-reactivity between Streptococcal substances and heart muscle (heart reactive antibodies) Sensitized T-lymphocytes may lead to cardiac injury Sensitized T-lymphocytes may lead to cardiac injury

JONES' CRITERIA FOR DIAGNOSIS OF RF: Major Manifestations Major Manifestations Carditis (friction rub, murmur, cardiomegaly, CHF) Carditis (friction rub, murmur, cardiomegaly, CHF) Arthritis (migratory polyarthritis, swollen, red, tender) Arthritis (migratory polyarthritis, swollen, red, tender) Chorea Chorea Subcutaneous nodules Subcutaneous nodules Erythema marginatum 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) Cardiac Disease (Rheumatic heart disease) Extra-Cardiac Disease Extra-Cardiac Disease

RHEUMATIC HEART DISEASE Rheumatic heart disease: all the heart layers are affected (pancarditis) 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 Aschoff ’ s Bodies within the myocardium. Gross features: Aschoff bodies are multiple tiny nodules (1-2 mm in diameter) Aschoff bodies are multiple tiny nodules (1-2 mm in diameter) Microscopic features: Aschoff body is a lesion composed of: Aschoff body is a lesion composed of: Fibrinoid necrosis ( destroyed fragmented collagen) Fibrinoid necrosis ( destroyed fragmented collagen) Surrounded by lymphocytes and histiocytes & Surrounded by lymphocytes and histiocytes & Aschoff cells (large mononuclear or multinuclear macrophages) Aschoff cells (large mononuclear or multinuclear macrophages)

Aschoff’s body Blood vessel fibrinoid degeneration Aschoff cells

Chronic phase: Over years or decades the Aschoff bodies undergo fibrous scarring Over years or decades the Aschoff bodies undergo fibrous scarring

2- Rheumatic Pericarditis: Acute phase: Aschoff bodies are formed accompanied by serofibrinous inflammation. 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 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 i- Acute phase: Aschoff bodies develop in the endocardium ii- Chronic phase: healing results in a white patch 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. 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: Mitral & Aortic Valves Pathology: Thickening of valve leaflet, especially along the lines of closure Thickening of valve leaflet, especially along the lines of closure Fusion of commissures Fusion of commissures Result is mitral or aortic stenosis, insufficiency, or both Result is mitral or aortic stenosis, insufficiency, or both

Rheumatic Mitral Stenosis Thick valve leaflet Fusion of commisures

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. 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 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. 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 Rheumatic arteritis: affecting the coronaries, renal, mesenteric and cerebral arteries Pleurisy and peritonitis: serofibrinous type Pleurisy and peritonitis: serofibrinous type

PERICARDIAL DISEASES I. PERICARDITIS Inflammation of the pericardium Causes Causes MI, Staphylococcus, tumor, TB, uremia MI, Staphylococcus, tumor, TB, uremia

II. PERICARDIAL EFFUSION Serous fluid in pericardial sac Serous fluid in pericardial sac Usual cause: Chronic Heart Failure Usual cause: Chronic Heart Failure

III. HEMOPERICARDIUM Myocardial rupture from MI Myocardial rupture from MI Trauma Trauma Bleeding from infection, tumor, etc. Bleeding from infection, tumor, etc. Haemorrhage from aorta Haemorrhage from aorta

Hemopericardium