Pathology Handbook

Anti Cardiolipin



Clinical Indications

Antiphospholipid syndrome (venous and arterial thrombosis, stroke, TIA and multiple-infarct dementia in the absence of other features of lupus)
Recurrent foetal loss

Please note: Transient antibodies may be found after viral infections. It is therefore important to send a repeat sample after 12 weeks to confirm a diagnosis of anti phospholipid syndrome. The patient should also be tested for the presence of Lupus Anticoagulant (if the patient is not on anticoagulant treatment)

Test Includes

Detection of IgG and IgM autoantibodies against Cardiolipin with added Beta 2 Glycoprotein 1.

Request Form 

Request via ICE


Assay performed daily; Monday to Friday.

Specific Criteria

It is essential to provide relevant clinical information.

Turnaround Time

All samples are generally sent to  referral laboratory within 3 working days of receipt in the laboratory. The assay is performed daily; Monday to Friday.




7 ml


Vacutainer red top


Samples should be transported to the laboratory immediately

Lab Handling

Aliquot and store at 4-8°C prior to testing and at -20°C or below for up to 1 month after receipt.

Causes for Rejection

Unlabelled/inadequately labelled sample
Inadequately completed request form
Delay in sample reaching laboratory

Reference Range

Negative: < 10 PLU/mL

Equivocal: 10-40 PLU/mL

Positive: > 40 PLU/mL

The level of antibody in units is not directly related to the severity of disease. However, weak positive results are of doubtful significance.