Diagnosis
Diagnosis of scarlet fever is clinical. The blood test shows marked leukocytosis with neutrophilia and conservated or increased eosinophils, high erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) (both indications of inflammation), and elevation of antistreptolysin O titer. Blood culture is rarely positive but the streptococci can usually be demonstrated in throat culture.
Read more about this topic: Scarlet-fever