Pathology Handbook

Antithrombin assay

Synonyms

AA, AT3, Antithrombin 3

Clinical Indications

Clinical / family history of thrombotic episodes

Please refer to Thrombophilia clinic or d/w Consultant haematologist BEFORE making request.

NOT available immediately post thrombosis or while patient on anticoagulant therapy.

It is strongly suggested to request a Thrombophilia screen rather than Antithrombin assay unless investigating a known low Antithrombin

Request Form 

Request via ICE

Availability

Mon - Fri 9AM to 4PM

Specific Criteria

Patient should be bled with minimal stasis

Patient Preparation

Patient should ideally be at rest and not in acute phase reaction

Turnaround Time

2 weeks

Specimen

Fresh citrated Blood (within 2 hours of collection)

Volume

4.5 ml blue citrated blood

Container

Blue capped vacutainer tube

Vacutainer blue top

Collection

Samples should be taken with minimal stasis and taken to the laboratory as soon as possible

Causes for Rejection

Underfilled, clotted or haemolysed samples

Reference Range

See patient test report