Study of platelet indices and their role in evaluation of thrombocytopenia

Thrombocytopenia may result from mechanisms such as marrow hypoplasia, increased destruction of platelets, and splenic sequestration. The gold standard method for discriminating the causes of thrombocytopenia is bone marrow examination, but it is invasive and expensive. Therefore, an alternative method should be introduced as a first-line diagnostic procedure. Of late, the automated blood cell analyzer has made it possible to assess the cause of thrombocytopenia through various machine-derived parameters, known as platelet indices, which include the mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT), which are provided as a part of routine complete blood count.

The objectives of the present study are to study the variation and effectiveness of platelet indices in establishing the etiology of thrombocytopenia.

An observational, prospective, and comparative study was conducted on 134 patients with thrombocytopenia, and 67 cases were taken as the normal group. The study group was classified into two groups: hypo-productive and hyper-destructive. Platelet indices were recorded and compared in the two groups along with the normal group.

The mean platelet count (10^3 μL) in the normal, hypo-productive, and hyper-destructive groups was 232.03 ± 74.84, 73.00 ± 36.52, and 68.28 ± 38.24, respectively. The MPV and mean PCT in the normal, hypo-productive, and hyper-destructive groups were 9.46 ± 1.68fL, 8.99 ± 1.49fL, and 11.35 ± 1.35fL and 0.22 ± 0.06%, 0.07 ± 0.04%, and 0.08 ± 0.05%, respectively. The mean PDW in the normal, hypo-productive, and hyper-destructive groups was 15.66 ± 1.76fL, 17.63 ± 1.01fL, and 18.32 ± 1.10fL, respectively.

In the present study, platelet indices such as MPV, PCT, and PDW are higher in the hyper-destructive group and may discriminate hyper-destructive from hypo-productive causes of thrombocytopenia.