King Abdulaziz University, Jeddah, Saudi Arabia.
The McGill University Health Centre, Montreal, Canada.
Thromb J. 2014 Dec 16;12(1):30. doi: 10.1186/s12959-014-0030-0. eCollection 2014.
Homocysteine is an amino acid that is toxic to vascular endothelial cells, and plasma elevations have been associated with venous thromboembolism. Severe hyperhomocysteinemia (>100 μmol/L) may result from mutations in the genes coding for enzymes in the trans-sulfuration or the folate/vitamin B12-dependent re-methylation pathways. Here, we report the case of a young woman with severe, recurrent thrombo-embolic events associated with severe hyperhomocysteinemia (111 μmol/L). We identified a homozygous mutation in the cystathionine β -synthase gene (p.I278T) and the presence of the Factor V Leiden mutation. Family study shows segregation of elevated homocysteine in heterozygous relatives for the mutation in the cystathionine β -synthase gene. Management consisted of anticoagulation with warfarin and supplementation with folate, vitamin B6 (pyridoxine) and vitamin B12. After twelve years of follow-up, plasma homocysteine levels remain in the moderate range (~20 μmol/L, reference range 8-12 μmol/L) and no further thromboembolic events were identified.
同型半胱氨酸是一种对血管内皮细胞有毒的氨基酸，其血浆水平升高与静脉血栓栓塞有关。严重的高同型半胱氨酸血症（>100 μmol/L）可能是由于编码转硫途径或叶酸/维生素 B12 依赖性再甲基化途径中酶的基因突变所致。在这里，我们报告了一例年轻女性严重、复发性血栓栓塞事件与严重高同型半胱氨酸血症（111 μmol/L）相关的病例。我们发现胱硫醚β-合成酶基因（p.I278T）的纯合突变和因子 V 莱顿突变的存在。家族研究显示突变胱硫醚β-合成酶基因的杂合子亲属中同型半胱氨酸升高的分离。治疗包括华法林抗凝和叶酸、维生素 B6（吡哆醇）和维生素 B12 的补充。经过 12 年的随访，血浆同型半胱氨酸水平仍保持在中等范围（~20 μmol/L，参考范围 8-12 μmol/L），未发现进一步的血栓栓塞事件。
