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Alias: Protein C, Protein S and Antithrombin (AT).

Discipline: Coagulation

Test information: Thrombophilia screening should start with an affected relative.
Current guidelines advise screening other family members only if a defect is identified in a first degree relative.
Thrombophilia screening should be performed when a patient is stable (unless clinically urgent), even if on Warfarin, as results can be unsatisfactory if performed close to an event, due to the acute phase response.

Specimen Type(s)
  • Blood;
Other Acceptable Specimen Type(s)
3 x blue top citrate sample (blue tube 3.2% tri-sodium citrate).
1 X Purple top EDTA sample for Full blood count
1x Gold top serum tube for anti-cardiolypin.
Specimen Container - Adult
  • Light Blue Top BD;
Specimen Container - Paediatric
  • N/A;
  • N/A;
Part of a test profile?
Thrombophilia screen
Volume (min) of sample to be sent to laboratory
Patient Preparation, Sample Handling and Transport
Completion and submission of a Thrombophilia Investigation Sheet and sent with accompanying samples will speed appropriate testing and return of results - please contact lab directly on 01872 25 (2502) if a copy is required.
Maximum add on time
4 hours
Units and Reference Ranges / Interpretation
Linear range: Antithrombin 7.2-150%, Protein C 5-120%, Proteins S 7.3-150
All thrombophilia results outside normal ranges are referred to Consultant Haematologist for review.
UKAS number
UKAS accredited test?
Please note- Prothrombin Gene mutation is often tested as part of a wider thrombophilia investigation, it is not an accredited test.

If you have any queries about a test or results interpretation please contact us.

Last updated: 09-05-2024