Platelets
Disclaimer: Information on this page is for educational purposes. Consult a physician to interpret your test results. Health Vault helps track biomarker trends but does not replace medical advice.
What This Test Measures
Platelets (thrombocytes) are small blood cells involved in clotting and hemostasis. They form a platelet plug at sites of vascular injury and activate the coagulation cascade.
Platelet count is part of the CBC and is critical for assessing bleeding risk (when low) and thrombosis risk (when markedly elevated). Thrombocytopenia below 50 × 10⁹/L increases spontaneous bleeding risk.
Beyond count, platelet size (MPV) and functional activity matter, especially before surgery and during anticoagulant therapy.
Normal Ranges
| Group | Reference Range |
|---|---|
| Men | 150–400 × 10⁹/L |
| Women | 150–400 × 10⁹/L |
| Children | 150–450 × 10⁹/L |
Reference ranges may vary by laboratory and assay method.
Causes of High Levels
- Reactive thrombocytosis (post-surgery, infection, inflammation)
- Iron deficiency anemia
- Essential thrombocythemia (myeloproliferative neoplasm)
- Post-splenectomy
- Inflammatory diseases and malignancy
Causes of Low Levels
- Immune thrombocytopenic purpura (ITP)
- Viral infections (hepatitis C, HIV, dengue)
- Aplastic anemia, chemotherapy
- Disseminated intravascular coagulation (DIC)
- Hypersplenism, alcoholic liver cirrhosis
Test Preparation
- No preparation required
- Report bleeding, bruising, and anticoagulant use
- Avoid aspirin for 48 hours unless otherwise directed
Related Biomarkers
| Biomarker | Relationship |
|---|---|
| Fibrinogen | Key clotting factor |
| D-Dimer | Fibrinolysis and thrombosis marker |
| Prothrombin Time (PT) | Extrinsic coagulation pathway assessment |
FAQ
How often should I take this test?
Annually; before surgery; with hematologic conditions — per physician schedule.
What should I do if my result is abnormal?
With thrombocytopenia, avoid trauma and unnecessary NSAIDs. Seek urgent care for bleeding.
Last updated: June 2026