?Scarlet FeverClassificationof Streptococci Virulence ofGroup Aβ-hemolytic streptococciEpidemiology Pathophysiology Clinical Manifestations ComplicationsLab studiesDiagnosis &DifferentialDiagnosis TreatmentPrognosisDIVISIONOFINFECTIOUS DISEASE ANDGASTROENTEROLOGY
Scarlet Fever DIVISION O F INFECTIO US DISEAS E AND GASTRO ENT E RO LO GY □ Classification of Streptococci □ Virulence of Group A β - hemolytic streptococci □ Epidemiology □ Pathophysiology □ Clinical Manifestations □ Complications □ Lab studies □ Diagnosis & Differential Diagnosis □ Treatment □ Prognosis
Classification of the GenusStreptococcusComplete Hemolysisβ- hemolytic streptococciPartially Hemolysis:α- hemolytic streptococci No hemolysis:Blood Agar- hemolytic streptococciDIVISION OFINFECTIOUS DISEASE AND GASTROENTEROLOGY
□ C o m p l e t e H e m o l ys i s : β- hemolytic streptococci □ P a r t i a l l y H e m o l ys i s : α- hemolytic streptococci □ No h e m o l ys i s : γ- hemolytic streptococci Classification of the Genus Streptococcus DIVISION O F INFECTIO US DISEAS E AND GASTRO ENT E RO LO GY
Classification ofthe Genus Streptococcus8O3二中alphabetagammaDifferent hemolyticreactionsComplete hemolysis =betahemolysinsproduce a clear, yellowzonealphahemolysinsproduceagreenPartial hemolysis =discolorationzoneNo hemolysis=nohemolysins,nozoneDIVISION OFINFECTIOUS DISEASE ANDGASTROENTEROLOGY
Classification of the Genus Streptococcus Differ en t h e m o l y t i c r e a c t i o n s C o m p l e t e h e m o l ys i s = beta hemolysins produce a clear,yellow zone DIVISION O F INFECTIO US DISEAS E AND GASTRO ENT E RO LO GY P art i a l h e m o l ys i s = N o h e m o l ys i s = alpha hemolysins produce a green discolorationzone no hemolysins, no zone
Classification of the Genus StreptococcusStreptococciβComplete Hemolysisβ- hemolytic streptococciPartially Hemolysisα- hemolytic streptococci1Nonhemolysis-hemolytic streptococciThe β- hemolytic streptococci is the most importantbecause it is one of the major etiologic pathogen of humanDIVISION OFINFECTIOUS DISEASE ANDGASTROENTEROLOGY
Classification of the Genus Streptococcus S t r e p t o c o c c i C o m p l e t e H e m o l ys i s β- hemolytic streptococci P ar t ially H e m o l ys i s α- hemolytic streptococci N o n h e m o l ys i s γ- hemolytic streptococci The β- hemolytic streptococci is the mos t important b eca u se it is on e of the major etiologic p a th ogen of h u ma n DIVISION O F INFECTIO US DISEAS E AND GASTRO ENT E RO LO GY
Furtherclassification ofβ?hemolytic streptococcicapsuleGroup-specificcarbohydrateprotein antigensβ- hemolyticcarbohydratesstreptococciarepeptidoglycandividedinto 20cell coatgroupscytoplasmalphabetically:AtoHcell wallKto VSketch Map of Structureof StreptococciGroup A(StreptococcusPyogenesS. PyogenesDIVISION OFINFECTIOUS DISEASE AND GASTROENTEROLOGY
Further classification of β- hemolytic streptococci β- hemolytic streptococci are divided into 20 groups alphabetically: A t o H K t o V G r o u p A (Streptococcus Pyogenes) S. Pyogenes Group-specific carbohydrate DIVISION O F INFECTIO US DISEAS E AND GASTRO ENT E RO LO GY