Platelets

The normal reference range for Platelets is Platelets are typically 150-400 x10^9/L. They are essential for clotting, so very low counts raise bleeding risk and very high counts can raise clotting risk. A common pitfall is "pseudothrombocytopenia" — a falsely low count from platelet clumping in the sample tube.. Reference ranges may vary between laboratories, so always consult your healthcare provider for interpretation.

Screens for bleeding disorders or clotting risks and provides information about bone marrow function and is a risk factor for cardiovascular diseases.

A high platelet count (thrombocytosis) is most often reactive — a temporary response to infection, inflammation, iron deficiency, recent bleeding, surgery or removal of the spleen. Less commonly it is primary, caused by a bone marrow disorder such as essential thrombocythaemia, where the count is persistently high and may need treatment to reduce clotting risk.

A low platelet count (thrombocytopenia) can result from increased destruction (immune thrombocytopenia, ITP), reduced production (bone marrow disorders, chemotherapy, B12 or folate deficiency), or pooling in an enlarged spleen (often from liver disease). Viral infections, excess alcohol and some medications also lower it, and a mild dip is normal in pregnancy. A falsely low result from clumping should always be excluded by repeating the test.

Platelets are reported in every full blood count. A very high or very low count, or a falling trend, is investigated with a blood film (to check for clumping and abnormal cells) and repeated, sometimes in a different tube. Counts are monitored closely during chemotherapy and in liver disease.