Rheumatic fever is an acute immunologically mediated multisystemic inflammatory disease that occurs a few weeks after an episode of group A streptococcal pharyngitis. It has five menifestation: 1) Migratory polyarthritis. 2) Pancarditis. 3) Subcuteneous nodule. Erythema marginatum of skin. 4) Sydenhum korea. Pathogenesis: 1. Pharyngitis or sore throat by group A,heamolytic streptococcus, 2.Immunoresponse to streptococcal antigen(capsule,protein and membrane antigen) 3.Cross reaction of the antibody with the following structure of heart(cardiac sarcolema,myocardial tissue,heart valve). 4)Type-2 hypersensitivity reaction 5) Multisystemic focal inflammatory reaction in connective tissue.

Morphology of acute rheumatic fever: During acute rheumatic fever,focal inflammatory lesions are found in various tissue.Distinctive lesions occur in the heart called ashcoff bodies.Ashcoff bodies consists of foci of lymphocytes occationally plasma cells and macrophages. During rheumatic fever ,diffuse inflammation and ashcoff bodies may be found in any of the layers of the heart causing pericarditis,myocarditis or endocarditis. Inflammation of the endocardium and the left sided valves typically results in fibrinoid necrosis within the cusps or along the tendinous cardis.

Overlying these necrotic foci are small vegetations called verrucae along lines of closure.These vegetations place rheumatic heart disease with in a small group of disorderthat are associated with vegetative valve disease,each with its occur characteristic morphologic features. Complication of rheumatic fever: 1) Pericarditis 2) Pericardial effusion. 3)Mitral valve disease: Mitral stenosis or mitral regurgitation. 4)Aortic valve regurgitation: Aortic stenosis or aortic regurgitation. Rarely: Pulmonary stenosis,Pulmonary regurgitation,Tricuspid stenosis,Tricuspid regurgitation. Fate of rheumatic fever: •Complete recovery within 6 weeks •Recurrent attack is common and produce additional scaring. •Chronic rheumatic heart disease