Childhood myelodysplastic syndrome associated with an acquired Bernard-Soulier–like platelet dysfunction

A 9-year-old girl was admitted because of diffuse ecchymosis, progressive asthenia, pallor, and fever occurring over the course of 2 weeks. She had a history of abnormal bruising during the previous 9 months. Her blood counts showed severe anemia (hemoglobin, 7.6 g/dL), low reticulocyte count (16 500 cells/μL), and thrombocytopenia (28 000 cells/μL). Standard coagulation tests were normal. Morphologic examination of peripheral blood confirmed thrombocytopenia and revealed the presence of giant platelets (panel A), with no significant abnormalities in lymphocytes and polymorphonuclear cells. Cytofluorimetric analysis of platelet-rich plasma confirmed the predominant population of large platelets that lacked CD42b (glycoprotein Ib [GpIb]) expression on their surface. Their expression of CD41a (GpIIb) and CD61 (GpIIIa) was slightly increased. These data suggested a diagnosis of Bernard-Soulier syndrome. However, parents and siblings were healthy, and their platelets were morphologically and immunophenotypically normal.

Because of hyporegenerative anemia, a morphologic and cytofluorimetric analysis of the patient's bone marrow was performed, which revealed the presence of a severe trilineage dysplasia and 15% of CD33⁺, CD13⁺, CD117⁺, and CD34^– myeloid blasts (panel B). Cytogenetic analysis of the bone marrow showed monosomy of chromosome 7 in all metaphases. Our data are consistent with childhood myelodysplastic syndrome associated with an acquired Bernard-Soulier–like platelet dysfunction.