新生儿筛查确诊甲硫氨酸腺苷转移酶Ⅰ/Ⅲ缺陷症5例临床分析

Clinical analysis of methionine adenosyltransferase Ⅰ/Ⅲ deficiency in 5 confirmed cases in neonatal screening

目的探讨甲硫氨酸腺苷转移酶Ⅰ/Ⅲ缺陷症的临床和基因变异特点.方法回顾分析串联质谱新生儿筛查发现的5例甲硫氨酸腺苷转移酶Ⅰ/Ⅲ缺陷患儿的临床资料及基因检测.结果22万例新生儿筛查中发现甲硫氨酸腺苷转移酶Ⅰ/Ⅲ缺陷5例,发病率为1/44000.5例患儿中,3例血甲硫氨酸在70~150μmol/L之间.基因检测2例符合常染色体显性遗传、1例符合常染色体隐性遗传.3例随访至今预后良好,另2例血甲硫氨酸持续>500μmol/L;予以特殊饮食治疗,1例头颅磁共振成像和肝功能异常,1例伴有微缺失综合征,发育落后.结论甲硫氨酸腺苷转移酶Ⅰ/Ⅲ缺陷可通过串联质谱新生儿筛查结合基因检测而早期诊断,需要长期随访.

Objective To explore the clinical and gene variation characteristics of methionine adenosyltransferaseⅠ/Ⅲ deficiency.Methods The clinical data and gene detection of methionine adenosyltransferaseⅠ/Ⅲ deficiency in 5 newborns found by tandem mass spectrometry in neonatal screening were retrospectively analyzed.Results In the 220000 newborns screened,5 cases of methionine adenosyltransferaseⅠ/Ⅲ deficiency were found and an incidence rate was 1/44000.In the 5 newborns,the concentrations of methionine were 70~150μmol/L in 3 newborns,among whom 2 were autosomal dominant inheritance and one was autosomal recessive inheritance and all of them had a good prognosis.The blood methionine concentrations of the other 2 newborns were continuously greater than 500μmol/L and they were autosomal recessive inheritance.These 2 newborns were treated with special diet.During follow-up,1 patient had abnormal cranial magnetic resonance and abnormal liver function,and 1 patient had microdeletion syndrome and developmental retardation.Conclusion Methionine adenosyltransferaseⅠ/Ⅲ deficiency can be diagnosed early by tandem mass spectrometry combined with gene detection and the disease requires long-term follow-up.