Role of platelet volume indices in the differential diagnosis of thrombocytopenia: a simple and inexpensive method.

Thrombocytopenia may result from hypoproliferation in marrow, or peripheral destruction of platelets. Distinction between these two categories is usually made by bone marrow examination. Some studies in literature hint that platelet volume indices are differentially altered in various causes of thrombocytopenia. The present study was aimed at investigating the role of platelet volume indices in the differential diagnosis of thrombocytopenia. Sixty healthy controls and 60 patients (study group) with thrombocytopenia (platelet count < 150 x 10(9)/l) were included in the study. The study group was divided into two categories: hypoproliferative (megaloblastic and non-megaloblastic) and destructive thrombocytopenia. Clinical features, platelet counts and platelet indices were studied in both these categories, and statistical analysis was performed. Platelet counts in the three categories of thrombocytopenia were statistically not different. All the three platelet volume indices were significantly higher in megaloblastic group as compared to the non-megaloblastic hypoproliferative category. Platelet distribution width (PDW) was significantly different between destructive thrombocytopenia and non-megaloblastic hypoproliferative groups. In conclusion, we recommend the division of hypoproliferative category of thrombocytopenia into megaloblastic and non-megaloblastic types. Alterations in platelet indices, especially PDW can differentiate non-megaloblastic hypoproliferative category from both the destructive and megaloblastic thrombocytopenia category. These simple indices can be routinely used in the initial evaluation of a patient with thrombocytopenia.