How far are the platelet indices mirror image of mechanism of thrombocytopenia-mystery still remains?
Keywords:Correlation, Platelet count and indices, Pathogenetic mechanism, Thrombocytopenia
Background: Evaluation of thrombocytopenia requires thorough clinical history, examination, complete hemogram, including platelet indices and bone marrow study whenever indicated. The etiopathogenetic mechanism decides patient management. The aim was to study relationship between thrombocytopenia and platelet indices with respect to underlying mechanisms.
Methods: Totally 100 thrombocytopenic patients with sufficient clinico-hematological workup were included in our study. Results were confirmed by peripheral smear examination and manual platelet count wherever necessary. Similar data during the year 2012 were collected from 100 controls and compared.
Results: Patients were grouped based on mechanism-hypoproduction 15 (megaloblastic anemia 8, myelodysplastic syndrome 1, leukemia 6), hyperdestruction 4 (immune thrombocytopenic purpura), hyperspleenism 19 (chronic dengue 10, chronic malaria 6, chronic liver disease 3) and mixed 62 (chronic dengue 29, chronic malaria 24, thalassemia on regular transfusion 3, sepsis 4, disseminated intravascular coagulopathy 2).
Conclusion: (1) Platelet indices showed inverse relationship-increase (mean platelet volume [MPV] r = −0.805, platelet distribution width [PDW] r = –0.996) with decreasing platelet count in most increased destruction cases, (2) linear relationship (MPV r = 0.84, PDW r = 0.37) was seen in most hypoproduction cases. p values were also calculated, (3) variable results were obtained in hyperspleenism, mixed and few of above two groups, (4) platelet indices provide important information about platelet kinetics. However, relationship with platelet count is helpful but not always confirmative of mechanism of thrombocytopenias.
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