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Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,STREPTOCOCCI,Systemic Bactreiology,Words must to be known,Group A streptococcus,(S.pyogenes,),Lancefield groups,Hemolysis(alpha,beta,gamma),Bacitracin,susceptibility test,M,T,R proteins,Streptolysins O and S,F protein/lipoteichoic acid,Rheumatic fever/carditis/arthritis,Glomerulonephritis,Scarlet fever,Toxic shock-like syndrome/bacteremia,“Flesh-eating bacteria”,Pyrogenic toxin,Erythrogenic toxin,Group B streptococcus(,S.agalactiae,),Neonatal septicemia/meningitis,CAMP test,Hippurate hydrolysis test,Group D streptococcus,Urinary tract infection/endocarditis,Bile-esculin test,Enterococci,Non-enterococci,Large colony,Minute colony,Viridans streptococci,Dental caries/endocarditis,Streptococcus pyogenes,During the infection,this bacteria produce pus,-One of the most important pathogens,-Gram positive cocci in chains,-Lancefield Serological Group A,-Beta Hemolytic on blood agar,Gram Stain of,S.pyogenes,Streptcoccus pyogenes,S.agalactia,S.peumoniae,Hemolysis on Blood Agar Plates,Beta hemolysis,-organisms excretes potent hemoysins which completely lyse RBCs(complete hemolysis)thus a clear zone appears around colony.,S.pyogenes,Alpha hemolysis,-organism excretes hemolysins which partially break down rbc (incomplete hemolysis)thus a greenish zone appears around colony.,S.pneumoniae,S.pyogenes,S.pneumonia,Beta hemolysis,Alpha hemolysis,Streptococci,facultative anaerobe,Gram-positive,chains or pairs,catalase,negative,(staphylococci are,catalase,positive),Streptococcus,in chains(Gram stain),Streptococci,Lancefield,groups,one or more species per group,carbohydrate antigens,Groupable,streptococci,1-A,B and D,frequent,2-C,G,F,less frequent,Non-groupable,1-,S.pneumoniae,pneumonia,2-viridans streptococci,e.g.,S.mutans,dental caries,hemolysis reaction-sheep blood agar,a-,(beta-,),complete clearing,A and B,b-,(alpha-,),partial hemolysis,green color,c-(gamma-,),no lysis,White colonies,Hemolysis,1-Groups A an B,-,hemolysis,2-Group D,or-,hemolysis,3-,S.pneumoniae,and,S.viridans,-,hemolysis,hemolysis reaction,+,one characteristic,presumptive identification,Group A streptococcus,(,S.pyogenes,),Group A streptococcal infections affect all ages,peak incidence at 5-15 years of age,S.pyogenes,suppurative,1-non-invasive,-pharyngitis,-skin infection,impetigo,2-invasive bacteremia,-toxic shock-like syndrome,-flesh eating bacteria,-pyrogenic toxin,Pyrogenic toxin,Streptococcus pyogenes,and,Staphylococcus aureus,express,pyrogenic toxin superantigens(PTSAgs),that are associated with toxic shock syndrome(TSS)and staphylococcal food poisoning(SFP).,Most PTSAgs cause TSS in deep-tissue infections,whereas only TSS toxin 1(TSST-1)is associated with menstrual,vaginal TSS.,In contrast,SFP has been linked only with staphylococcal,enterotoxins,(SEs).,Pyrogenic toxin,Because of the differential abilities of PTSAgs to cause systemic or localized symptoms in a site-dependent manner,these toxins have abilities to cross mucosal barriers.,The activity of three PTSAgs when delivered,orally,vaginally,or,intravenously,to rabbits and orally to monkeys in some experimental studies.,Pyrogenic toxin,1-superantigen,2-T cell mitogen,3-activates immune system,Scarlet fever,-rash,-erythrogenic toxin,non-suppurative,rheumatic fever,-inflammatory disease,-life threatening,-chronic sequalae,fever,heart,joints,rheumatic NOT rheumatoid arthritis,Rheumatic fever,is an inflammatory disease that occurs following a Group A streptococcal infection,(such as strep throat or scarlet fever).Believed to be caused by antibody cross-reactivity that can involve the heart,joints,skin,and brain,the illness typically develops two to three weeks after a streptococcal infection.Acute rheumatic fever commonly appears in children between the ages of 5 and 15,with only 20%of first-time attacks occurring in adults.The illness is so named because of its similarity in presentation to rheumatism.,Rheumatic fever-etiology,M protein,cross-reacts heart myosin,autoimmunity,Cell wall antigens,poorly digested,in vivo,persist indefinitely,Rheumatic fever,Penicillin,terminates pharyngitis,decreases carditis,Acute glomerulonephritis,immune complex disease of kidney,Major pathogenesis factors,lipoteichoic acid/F protein,fimbriae,binds to epithelial cells,M protein,anti-phagocytic,S.pyogenes,fibronectin,lipoteichoic acid/F-protein,epithelial cells,M protein,M protein,fibrinogen,r,r,r,peptidoglycan,r,r,r,IgG,Complement,IMMUNE,NON-IMMUNE,M protein,major target,natural immunity,strain variation,antigenicity,re-infection,occurs with different strain,Capsules,Anti-phagocytic,mucoid strains,Isolation and identification,-,hemolytic colonies,bacitracin inhibits growth,-,hemolytic colonies,group A antigen,Bacitracin,is a mixture of related cyclic polypeptides produced by organisms of the licheniformis group of,Bac
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