Transient Myeloproliferative Disorder in a Neonate without Down Syndrome—A Rare Case Report and Review of the Literature

Abstract

Transient myeloproliferative disorder (TMD) is a self-limiting disorder characteristically seen in neonates with Down syndrome with or without somatic mosaicism. Trisomy-21 limited to the hematopoietic lineage alone has been described; awareness of which is very important for appropriate evaluation and counseling in phenotypically normal children.We report a newborn with TMD who presented at birth with intracranial bleed secondary to thrombocytopenia. Peripheral smear showed 10% blasts and flow cytometry further revealed myeloid blasts of megakaryocytic lineage. The child had no phenotypic features of Down syndrome.Cytogenetic analysis (fluorescence in situ hybridization) and the conventional karyotyping from peripheral blood showed trisomy-21 in blast cells and the findings completely cleared with peripheral clearance of blasts. The possibility of Down syndrome with mosaicism was considered, however, repeat conventional karyotyping from peripheral blood at D36 and D60 of life was normal, suggesting the gain of chromosome 21 was restricted to the TMD clones.The child was supported with irradiated platelet transfusions and adequate hydration. Spontaneous resolution with resolution of cytopenias and peripheral clearance of blasts were noted from D10 of life. The child is neurologically normal and growing well.Very few reports of TMD in newborn babies without Down syndrome have been described in the literature. Awareness about the diagnostic entity of TMD even without Down syndrome would help in appropriate management and counseling.