A case report of a family with MYH9 gene mutation-related disease in an ethnic minority group and literature review.

BACKGROUND: May-Hegglin anomaly, a rare autosomal dominant disorder caused by MYH9 mutations, is characterized by the classic "triad" of thrombocytopenia, giant platelets, and granulocyte cytoplasmic inclusion bodies; some patients also present non-hematological symptoms. RESULTS: We reported a family of MYH9-related disease. The proband had microscopic hematuria, proteinuria, and thrombocytopenia on physical examination; blood smear re-examination showed giant platelets and Döhle-like bodies. His medical history included childhood epistaxis; his father had unexplained thrombocytopenia/proteinuria, and his younger brother had epistaxis/purpura/thrombocytopenia. Whole-exome sequencing (validated by Sanger sequencing) confirmed the diagnosis. CONCLUSIONS: Diagnosis of MYH9-related diseases depends on combined laboratory morphology and molecular biology. Routine blood tests and smear microscopy (identifying abnormal giant platelets/Döhle-like bodies) provide initial screening clues, while gene sequencing enables accurate diagnosis and pathogenesis clarification, forming a complete screening-to-confirmation diagnostic pathway.