Useful For

There are two possible tests for Protein S Antigen depending on the Coumadin medication status of the patient. It is important to order the appropriate test as described below. When the patient has:

1. Received NO Coumadin for the past two weeks, See 'Protein S Antigen, No Coumadin' (PROTSI)
2. On a STABLE Coumadin dose for at least two weeks, see ' Protein S Antigen, ON Coumadin' (PROT-SM)

Consult Hematology/Coagulation pathologist as needed (Marshfield Labs).