Megakaryocyte morphology and its impact in predicting response to steroid in immune thrombocytopenia.

Pathogenetic mechanisms of primary immune thrombocytopenia (ITP) include antibody-mediated destruction of platelets; cell-mediated destruction and suppressed thrombopoiesis. Various morphological changes in megakaryocytes are reported in ITP patients, but never these were correlated with the response to various forms of therapy. In the present study, we intended to find out the impact of megakaryocytic abnormalities on the response to steroid, the first line of treatment. The mean age of patients (n = 33) was 28.9 ± 7.6 years. Male/female ratio was 1/1.8. The mean platelet count at presentation was 5.6 ± 4.4 × 10(9)/L. 63.6% (21/33) patients showed response to steroid. The non-responders were given 50 mg/d TPO-RA (eltrombopag) in addition to steroid, to which, 83.3% (10/12) responded. Two-third patients (66.7%, n = 22) had normal megakaryocyte morphology. Those with abnormal morphology commonly had hypolobated forms and micromegakaryocytes. Ninety-five percent of steroid responders had normal megakaryocytic morphology. Among steroid non-responders, most patients (n = 10, 83.3%) had abnormal megakaryocytic morphology. 80% steroid non-responders with abnormal morphology responded to the addition of eltrombopag. The findings suggest that the abnormal megakaryocyte morphology can be an evidence of dominant pathogenetic mechanism and thereby can help us in individualizing the treatment of ITP.