A 28-year-old Hispanic man with a history of easy bruising and occasional episodes of epistaxis sought treatment for pancytopenia and splenomegaly. Peripheral blood smear and bone marrow analysis, electron microscopy, and next-generation sequencing were performed.
Large and agranular platelets were present in the peripheral blood. There was bone marrow fibrosis. Electron microscopy of the platelets showed absence of α-granules. Next-generation sequencing revealed a germline apparently homozygous nonsense variant in the NBEAL2 gene: c.5674C>T, p.Gln1892X (p.Q1829X).
The differential diagnosis of GPS includes a myeloid neoplasm such as myelodysplastic syndrome with bone marrow fibrosis. The availability of diagnostic genetic panels for hereditable platelet disorders can assist in the recognition of GPS and other platelet disorders. We also describe a previously unreported pathogenic germline homozygous nonsense variant in the NBEAL2 gene: c.5674C>T, p.Gln1892X (p.Q1829X) in a patient with GPS.
一名28岁的西班牙裔男子,有容易瘀伤和偶尔发作鼻出血的病史,他寻求治疗全血细胞减少症和脾肿大。外周血涂片和骨髓分析,电子显微镜,并进行了下一代测序。
外周血中存在大的和颗粒状的血小板。有骨髓纤维化。血小板的电子显微镜检查显示不存在α-颗粒。下一代测序揭示了NBEAL2基因中明显纯合的无义变体:c.5674C>T,p.Gln1892X(p.Q1829X)。
GPS的鉴别诊断包括骨髓性肿瘤,如骨髓增生异常综合征伴骨髓纤维化。遗传性血小板疾病的诊断遗传小组的可用性可以帮助识别GPS和其他血小板疾病。我们还描述了NBEAL2基因中以前未报道的致病性种系纯合无义变体:c.5674C>T,p.Gln1892X(p.Q1829X)在有GPS的患者中。