新生儿筛查发现4例MCCD患儿的临床和基因分析

摘要

目的 对4例经由新生儿筛查发现的不同临床类型的3-甲基巴豆酰辅酶A羧化酶缺乏症(3-methylcrotonyl-coenzyme A carboxylase deficiency,MCCD)患儿,周尿气相色谱质谱和基因分析证实其诊断.方法 对新生儿筛查中CADC+ C5OH＞ 0.6μmol/L的新生儿召回复查,同时检测其母亲的C4DC+ C5OH浓度.用尿气相色谱质谱分析对MCCD疑诊病例进行临床诊断,再通过基因分析进一步证实.结果 通过基因诊断确诊MCCD 3例,包括MCCD患儿1例,父源性MCCD 1例,母源性MCCD 1例.另有1例临床诊断的MCCD患儿经基因检测仅找到1个致病位点.结论 对新生儿筛查中发现的C4DC+C5OH增高的新生儿家系(包括母亲和父亲)应行MS/MS检测.疑似MCCD患者基因检测仅发现1个致病位点时不要轻易否定MCCD的诊断,建议定期随访.%Objective To analyze 4 child patients with 3-methylcrotonyl-coenzyme A carboxylase deficiency (MCCD) identified by neonatal screening and confirmed by urine gas chromatography-mass spectrometry (GC/MS) and genetic analysis.Methods Newborns whose C4DC + CSOH concentration was above 0.6 μmol/L in newborn screening were recalled for rescreening,and the CADC + C5OH concentrations in their mothers were detected.The child patients suspected with MCCD were further confirmed by urine GC/MS and genetic analysis.Results Three child patients were definitely diagnosed as MCCD by genetic analysis,including 1 MCCD,1 maternal MCCD and 1 paternal MCCD.The other 1 child patient suspected with MCCD had only one allele in MCCC1.Conclusion The mother and father of newborns with elevated C4DC + C5OH identified in neonatal screening should routinely perform MS / MS testing.When only one pathogenic locus is found in the suspected MCCD child patients by genetic analysis,they should be followed up regularly.