合并型甲基丙二酸血症并发肺动脉高压2例并文献复习

目的 探讨甲基丙二酸血症(MMA)与肺动脉高压的关系。 方法 回顾分析2例合并型MMA并发肺动脉高压患者的临床特点及基因特征,并复习相关文献,进行总结。 结果 2例患儿均尿甲基丙二酸水平升高及血同型半胱氨酸(Hcy)升高,符合合并型MMA的诊断;均具有肺动脉高压,并伴有持续性的肾脏损伤,其中1例伴有球形红细胞增多症,1例伴有眼球震颤。2例患儿基因检测显示均有MMACHC基因突变. 故为CblC缺陷型,1例基因突变型为:c.80A> G(p.Gln27Arg)/ c.609G> A(p.Trp203Ter)杂合型,1例为c80A>G(p.Gln27Arg)/ c.637G>T(p.Glu213Ter)杂合型,均最终死于肺动脉高压。 结论 儿童及青少年不明原因肺动脉高压应注意遗传代谢疾病的筛查,特别是对MMA的筛查。

Pulmonary hypertension in combined methylmalonic acidemia: a report of two cases and literature review

Objective To explore the relationship between methylmalonic acidemia(MMA)and pulmonary hypertension. Methods A retrospective analysis of 2 patients was carried out for clinical and genetic characteristics. Relevant literatures were reviewed and summarized. Results Metabolic screening showed MMA and hyperhomocysteinemia in two patients,which accorded with the diagnosis of combined MMA. Pulmonary hypertension and persistent renal abnormality were presented in both patients. One patient was accompanied with spherocytosis,and the other patient concurrently suffered from nystagmus. Both genetic analysis revealed a heterozygous MMACHC mutation(Cobalamin C type). The gene mutation of Case 1 was identified as c.80A> G(p.Gln27Arg)/ c.609G> A(p.Trp203Ter), and the gene mutation of Case 2 was identified as c80A>G(p.Gln27Arg)/ c.637G>T(p.Glu213Ter). Two patients died of pulmonary hypertension. Conclusion The screening of genetic metabolic diseases, especially MMA, should be performed for children and adolescents with unexplained pulmonary hypertension.