Group A beta haemolytic streptococci (GAbHS) cross reacts with?
Ans. a (Valves & Myocardium). (Ref. Harrison's principles of internal medicine, 18th Chapter 322.)Rheumatic heart disease# Group A beta haemolytic streptococci (GAbHS) is implicated as the cause of rheumatic valvular heart disease.# Age of occurence: 5-15 years.# Pathogenesis: Hypothesis of 'antigenic mimicry'; carbohydrate of GAbHS and glycoprotein of valves and streptococcal cell membrane, M protein sarcolemma and myocardial cell moieties have interactions i.e they cross react with each other. Antigenic relationships have been shown between capsular hyluronic acid & human synovial fluid, CE11 wall protein & myocardium, group A Carbohydrate & Cardiac valves, Cytoplasmic membrane antigens & vascular intima, & peptidoglycans & skin antigens.Streptococcal antigenCross-reacts withCapsular hyaluronic acidHuman Synovial FluidCytoplasmic membrane antigensVascular intimaPeptidoglycansSkin antigensCell wall proteinMyocardiumGroup A carbohydrateCardiac valves
Valves & myocardium
Annular ring
Endocardium
Pericardium
Infection