Unexplained chronic cytopenia: is it idiopathic cytopenia of undetermined significance or myelodysplastic syndrome.

Idiopathic cytopenia is a condition where there is a decrease in peripheral blood counts causing either anaemia, leucopoenia and thrombocytopaenia. Most cases of cytopenia reveal a cause on further workup. But very rarely, in some cases, a definitive cause could not be identified. Unexplained cytopenia becomes challenging and poses difficulty in diagnosis and management. Discriminating these groups of bone marrow failure disorders from myelodysplastic syndrome (MDS) becomes an important clinical question. We describe a case of a middle-aged Hispanic woman who presented with pancytopenia and on extensive workup did not reveal any specific cause. Her bone marrow examination revealed severely reduced megakaryocytes but with normal haemopoiesis of other lineages. Cytogenetics, flow cytometry, comprehensive next-generation whole genomic analysis did not reveal any abnormalities. She fit the criteria for idiopathic cytopenia of undetermined significance rather than MDS. She remained asymptomatic and her counts never improved with immunosuppressives or thrombopoietin mimetics.