Group A Streptoccocal Infection Flashcards
Onset of symptoms of Rheumatic fever or glomerulonephritis is associated with
Antibody response
During acute and convalascent phase of infection (group A infection) there should be
4 fold increase of Ab titer
Based on the neutralization hemolysin of Streptolysin O
Antistreptolysin O Titer
Antistreptolysin O Titer:
Titer is reported as:
Reciprocal of Highest Dilution showing NO HEMOLYSIS
Antistreptolysin O Titer:
Is expressed as
Todd Units
International Units
Antistreptolysin O Titer:
Normal Titer
< 166 Todd units
Antistreptolysin O Titer:
Moderately elevated (Adult)
> 240 Todd units
Antistreptolysin O Titer:
Moderately elevated (child)
> 320 Todd Units
Based on the Neutralization of depolymerizing activity of DNAse b
Anti DNAse B Test
Anti DNAse B Test
If there is no antibody present, the test will show
colorless
Anti DNAse B Test
Anti DNAse B is present, the test will show
green color remains
Stain used for Anti DNAse Test
Methyl green
Anti DNAse B test are graded:
4+
Intensity unchanged
Anti DNAse B Test
0
Loss of color
Slide agglutination screening test
Streptozyme Test
