Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
The so-called Lupus Anticoagulant (LA) is an auto-immune antibody found in the plasma/serum of some patients with Anti-Phospholipid Syndrome (APS) and a range of other situations. The anti-body is an anti-protein antibody and may occur transiently after a period of ill health or be persistant in APS. The antibody may be discovered by chance on pre-op screening tests – the antibody will in most cases cause a prolongation of the APTT. The test involves the use of two reagents, prepared from snake venom, phospholipid and calcium, with results being expressed as a ratio of screen/confirm. There is an association with increased risk of thrombosis in subjects with APS, this risk is increasingly significant if the subject is also positive for an Anti-B2Gp1 antibody. This test is part of the Thrombophilia Screen and is also performed when investigating a prolonged APTT. DOAC-REMOVE can also be added if the patient is on a DOAC such as Rviroxaban, Apixaban or Dabigatran. This must be stated in the clinical details.
Specimen container paediatric:
Light blue – sodium citrate
Specimen container adult:
Light blue – sodium citrate
Minimum volume paediatric:
1.3mL
Minimum volume adult:
2.7mL
Special requirements:
Tube must be correctly filled to line, to ensure correct ratio of blood to anticoagulant, ensure adequate mixing.
Sample stability:
4 hrs
Transport requirements:
Samples should be transported to lab without delay
Freq analysis:
Continuous
Add on test:
[email protected] (external)
Quality assurance:
UK NEQAS Blood Coagulation
Reference ranges:
Normal <1.2
Other info:
Assay to indicate presence of a lupus anticoagulant.