Coagulation screen

A coagulation screen is a combination of screening laboratory tests, designed to provide rapid non-specific information, which allows an initial broad categorization of haemostatic problems.

Process

The basic screen consists of:

platelet count
bleeding time for platelet function
PR for the tissue [factor pathway]
aPTT for the contact activation pathway
TCT or fibrinogen assay for final common pathway

Two other tests are regularly performed at the same time:

blood count, to detect other hematological abnormalities
liver function tests to exclude liver disease as a cause of coagulation factor deficiency

These tests may miss mild abnormalities but they will detect major disorders. The results of these screening tests, in conjunction with the clinical history, will then direct the selection of further, more detailed and specific coagulation tests, such as:

specific factor assays, like fibrin degradation products, D-dimer, thrombin time, platelet aggregation, or
specific factor inhibitor assays, like Protein C, TFPI, Antithrombin etc.