What does it mean when large and giant platelets are found in blood smear, rbc morphology and poikilocytosis? what causes large and giant platelets to show up?

Can be normal: Healthy persons can have normal juvenile large platelets. The more juvenile, the more larger platelets there are. EDTA in testing of MCV can cause clumping of platelets which may make them appear larger than normal. However, abnormally large platelets may be seen in Glanzman thrombasthenia, primary myelofibrosis or in myeloproliferative disorders. Discuss findings with your DR.