Platelet Distribution Width

Track Platelet Distribution Width for blood clotting diversity evaluation. Monitor platelet function for health optimization.

PDW · fL · aka PLATELET DIST WIDTH, PLATELET WIDTH, PDW-SD

What is Platelet Distribution Width?

Platelet Distribution Width (PDW) measures the variation in platelet size within your blood sample. This parameter indicates how uniform or diverse your platelets are in size, providing valuable information about platelet production and function. PDW reflects the heterogeneity of circulating platelets.

Why is it Tested?

Doctors order PDW as part of a complete blood count to evaluate platelet disorders, assess bone marrow function, and investigate bleeding or clotting problems. It helps distinguish between different causes of thrombocytopenia and provides insight into platelet production quality.

Normal Ranges

Reference ranges vary by lab and methodology, but general guidelines suggest:

  • Adults: 9–17% (when reported as coefficient of variation)

Note: Reference ranges may be expressed differently depending on measurement methodology (physical measurement vs. coefficient of variation).

Reference ranges vary by authority. Track yours across multiple standards with automatic unit conversions in LabsVault.

What do Abnormal Results Mean?

Abnormal results are not a diagnosis. Always discuss your results with a qualified healthcare provider before making any medical decisions.

Low PDW

Lower PDW indicates more uniform platelet sizes and may occur with:

  • Normal platelet production
  • Certain medications affecting platelet formation
  • Some inherited platelet disorders

High PDW

Elevated PDW indicates greater variation in platelet sizes and may suggest:

  • Active platelet production or regeneration
  • Myeloproliferative disorders
  • Immune thrombocytopenic purpura (ITP)
  • Hypersplenism
  • Bone marrow disorders
  • Recent bleeding with increased platelet production

How to Track Over Time

Tracking PDW helps monitor platelet disorders and treatment response, particularly in conditions affecting bone marrow function. Changes in PDW can indicate evolving platelet production abnormalities or response to therapies affecting platelet formation and release.

Track your Platelet Distribution Width results over time

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