Platelet function studies
Platelet aggregation at sites of vascular damage is a vital mechanism in the formation of a haemostatic plug. Inability to form a haemostatic plug successfully is linked to several inherited and acquired bleeding disorders. Platelet dysfunction may be inherited, acquired or induced by platelet-inhibiting agents, such as acetyl salicylic acid (aspirin). Studies indicate the platelet function assay (PFA) and template bleeding time (BT) give equivalent results in about 75 % of cases. Most of the discrepancies are patients with a normal BT and abnormal PFA test.
Aspirin and von Willebrand disease (vWD) are the most common causes for this discrepancy, since the bleeding time is very insensitive to aspirin and may miss as many as one third of cases of vWD.
Preoperative evaluation of platelet function Evaluation of women with menorrhagia
Determining the presence of drug-induced platelet dysfunction
Determining patient compliance with aspirin and other anti-platelet drugs
Determining platelet functionality in high-risk pregnancy
Evaluation of patients with suspected inherited or acquired platelet disorders, such as vWD
Evaluation of the bleeding patient
Monitoring DDAVP treatment in patients with type I vWD
COLL/ADP 60-120 s COLL/EPI 75-165 s
Additional platelet function tests are available on request.
Record last updated
August 26, 2025
Sample Container
2.7 ml Sodium citrate Vacutainers (Light blue top)
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- Clinical Biochemistry Ref: 8673
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- Infection & Immunity Sciences (Including Immunology, Virology, Microbiology and Histocompatibility and Immunogenetics ) Ref: 8659
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