Comprehensive Evaluation of Megakaryocyte Morphology and Its Correlation with Different Etiologies of Thrombocytopenia: A Bone Marrow Aspirate Study

Abstract

Background: Thrombocytopenia is a common hematological abnormality encountered in clinical practice and may arise from diverse etiologies including peripheral platelet destruction, impaired platelet production, bone marrow infiltration, nutritional deficiencies, infections, and hematological malignancies. Bone marrow examination remains an essential diagnostic tool in evaluating unexplained thrombocytopenia. Megakaryocytes, the platelet-producing cells of the bone marrow, exhibit distinct morphological alterations in various pathological conditions. Detailed assessment of megakaryocyte morphology can therefore provide valuable clues regarding the underlying etiology of thrombocytopenia.
Aim: To evaluate megakaryocyte morphology in bone marrow aspirates and correlate the morphological patterns with different etiologies of thrombocytopenia.
Methods: This prospective observational study was conducted in the Department of Pathology at Rajendra Institute of Medical Sciences (RIMS), Ranchi, over a duration of 1.5 years. A total of 73 patients presenting with thrombocytopenia and undergoing bone marrow aspiration were included. Bone marrow aspirate smears were stained with Leishman stain and examined for megakaryocyte number and morphology. Morphological parameters assessed included immature forms, dysplastic forms, bare nuclei, hypolobated megakaryocytes, micromegakaryocytes, emperipolesis, and platelet budding. Statistical analysis was performed using SPSS version 25.0. Chi-square test and ANOVA were applied wherever appropriate. A p-value <0.05 was considered statistically significant.
Results: Among the 73 cases, immune thrombocytopenic purpura (ITP) was the most common etiology (31.5%), followed by megaloblastic anemia (21.9%), acute leukemia (15.1%), aplastic anemia (12.3%), dengue-associated thrombocytopenia (9.6%), and myelodysplastic syndrome (9.6%). Increased megakaryocytes were predominantly observed in ITP cases, while reduced megakaryocytes were significantly associated with aplastic anemia and acute leukemia (p<0.001). Dysplastic megakaryocytes and micromegakaryocytes were significantly associated with myelodysplastic syndrome (p=0.002). Hypolobated forms were commonly observed in megaloblastic anemia and MDS. Emperipolesis was most frequent in ITP.
Conclusion: Megakaryocyte morphology provides important diagnostic insights in thrombocytopenia and correlates significantly with underlying etiologies. Bone marrow examination with careful morphological assessment of megakaryocytes remains an invaluable diagnostic approach for differentiating causes of thrombocytopenia.