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Screening for Lupus Anticoagulant

Alias: N/A

Discipline: Coagulation

Test information: To help evaluate a prolonged activated partial thromboplastin time (aPTT) and/or a thrombotic episode, to help determine the cause of recurrent fetal loss, as part of an evaluation for antiphospholipid syndrome. Not a diagnostic test for lupus (SLE).

Specimen Type(s)
  • Blood;
Other Acceptable Specimen Type(s)
Specimen Container - Adult
  • Light Blue Top BD;
Specimen Container - Paediatric
  • N/A;
  • N/A;
Part of a test profile?
Volume (min) of sample to be sent to laboratory
Patient Preparation, Sample Handling and Transport
Patients on heparin or heparin substitute (such as hirudin, danaparoid, or argatroban) anticoagulation therapy may have false-positive results for lupus.
To be transferred to laboratory within 4 hours to minimise platelet activation and neutralisation of any lupus anticoagulant.
Please make a note of any anticoagulants and/or bleeding/bruising symptoms.
Maximum add on time
Units and Reference Ranges / Interpretation
Screen Ratio greater than 2.0 - LA is strongly present,
Screen Ratio between 1.5-2.0 - LA is moderately present,
Screen Ratio between 1.2-1.5 - LA is weakly present
UKAS number
UKAS accredited test?
Direct-acting oral anticoagulants (DOACs) give false positive results.

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

Last updated: 03-05-2024