Mean platelet volume (MPV) is a machine-calculated measurement of the average size of platelets found in blood and is typically included in blood tests as part of the CBC. Since the average platelet size is larger when the body is producing increased numbers of platelets, the MPV test results can be used to make inferences about platelet production in bone marrow or platelet destruction problems.
MPV is higher when there is destruction of platelets. This may be seen in inflammatory bowel disease, immune thrombocytopenic purpura (ITP), myeloproliferative diseases and Bernard-Soulier syndrome. It may also be related to pre-eclampsia, and recovery from, transient hypoplasia.
Abnormally low MPV values correlate with thrombocytopenia when it is due to impaired production as in aplastic anemia. In addition, low MPV can correlate with abnormally small platelet size, sometimes a symptom of a spectrum referred to as Wiskott-Aldrich Syndrome (WAS), caused by a genetic mutation of the WAS gene.
A typical range of platelet volumes is 9.7–12.8 fL (femtolitre), equivalent to spheres 2.65 to 2.9 µm in diameter. Normal range is given as 7.5-11.5 fL.