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Protein S antigen, protein S functional.

Common Use:
To assess coagulation function, assist in the diagnosis of disorders such as disseminated intravascular coagulation (DIC), and evaluate oral anticoagulation therapy.

Plasma collected in a completely filled blue-top (3.2% sodium citrate) tube. If the patient’s hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted.

Normal Findings:
(Method: Clot detection)

Conventional Units
Adult70%–140% activity
Pediatric12%–60% activity
Note: The low end of “normal” is lower in patients younger than age 16 because of the immaturity of the liver.

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