Based on these findings, the diagnosis was revised from ITP to MYH9-RD.<h4>Discussion</h4>This case emphasizes that MYH9-RD should be considered in the differential diagnosis of unexplained thrombocytopenia, particularly when accompanied by characteristic cytological findings (e.g., giant platelets, blue inclusions in leukocytes) and a positive family history of related manifestations. The gene discussed is MYH9; the disease is autoimmune thrombocytopenic purpura.