Procedure:

-10 µ serum + 10 µ reagent of CRF (on black slid) then mix with rotation by hands for 3 min.
If -ve so the result is -ve in report
If +ve the titre is 6 mg/dl and we will repeat by the following values:

-The serum diluted by saline by the ratio 1 : 1 [mix1] .
Then take 10 µ of mix with 10 µ of reagent and rotate for 3 min.
If -ve so the result 6 mg/dl .
If +ve so the titre 12 mg/dl and repeat by the following values :

-The mix will diluted by saline by the ratio 1 : 1 or the serum diluted by saline by ratio
1 serum : 2 saline [mix2].
Then take 10 µ of mix2 with 10 µ reagent and rotate for 3 min.
If -ve so the result 12 mg/dl .
If +ve so the titre 24 mg/dl and repeat by the same steps.

-Titre of this test : 6 , 12 , 24 , 48
If the result leads to more than 48 the report is more than 48 and not higher titre values .

IMPORTANT COMMENT:

When testing new born children false -ve result are possible .

Lab Med