重庆市新生儿脂肪酸氧化代谢病筛查及确诊患儿随访分析

Screening for newborn fatty acid oxidation disorders in Chongqing and the follow-up of confirmed children

目的:了解重庆市脂肪酸氧化代谢病(FAOD)的发病率、临床特征、基因突变特点及预后。方法:采集2020年7月至2022年2月重庆医科大学附属妇女儿童医院新生儿疾病筛查中心招募的35374名新生儿的血液标本,采用串联质谱法检测干血斑中酰基肉碱谱,初筛阳性的患儿于2周内召回,进一步通过尿有机酸、血生化及基因检测等方法确诊,并对确诊患儿进行治疗和随访。结果:35374名新生儿初筛阳性267例,初筛阳性率为0.75%,基因确诊5例(FAOD发病率为1/7075),其中原发性肉碱缺乏症(PCD)3例(发病率为1/11791),短链酰基辅酶A脱氢酶缺乏症(SCADD)和极长链酰基辅酶A脱氢酶缺乏症(VLCADD)各1例(发病率均为1/35374)。3例PCD患儿SLC22A5基因突变以c.1400C>G和c.338G>A常见,c.621G>T为新突变,其中2例患儿予口服补充左卡尼汀,随访期间无临床表现;1例患儿拒绝治疗,于6月龄急性发作,补充左卡尼汀后症状好转,现生长发育正常。1例SCADD患儿检出ACADS基因复合杂合突变(c.417G>C和c.1054G>A),无临床表现。1例VLCADD患儿检出ACADVL基因复合杂合突变(c.1349G>A和c.1843C>T),新生儿期急性发作,治疗好转后予富含中链脂肪酸的奶粉喂养至今,随访期间发育正常。结论:重庆市FAOD发病率较高,其中PCD比例最高,VLCADD患儿临床表型严重。通过新生儿筛查,早诊断、早治疗有助于改善患儿预后。

Objective:To investigate the incidence,clinical characteristics,gene mutations and prognosis of fatty acid oxidation disorders(FAOD)in newborns in Chongqing.Methods:Blood samples were collected from 35374 newborns for screening of FAOD in the Neonatal Screening Center of Women and Children’s Hospital of Chongqing Medical University from July 2020 to February 2022.The acylcarnitine spectrum was detected by tandem mass spectrometry,the positive children in primary screening were recalled within 2 weeks,and the diagnosis of FAOD was confirmed by urine organic acid measurement,blood biochemistry testing and genetic analysis.The confirmed children were given early intervention,treatment and followed-up.Results:Among 35374 newborns,there were 267 positive children in primary screening,with a positive rate of 0.75%.Five children with FAOD were diagnosed by gene detection,with an incidence rate of 1/7075.Among them,there were 3 cases of primary carnitine deficiency(PCD,1/11791),1 case of short-chain acyl-CoA dehydrogenase deficiency(SCADD,1/35374)and 1 case of very long-chain acyl-CoA dehydrogenase deficiency(VLCADD,1/35374).The c.1400C>G and c.338G>A were the common mutations of SLC22A5 gene in 3 children with PCD,while c.621G>T was a novel mutation.There were no clinical manifestations during the follow-up period in 2 children with supplementation of L-carnitine.Another child with PCD did not follow the doctor’s advice of L-carnitine treatment,and had acute attack at the age of 6 months.The child recovered after treatment,and developed normally during the follow-up.The detected ACADS gene mutations were c.417G>C and c.1054G>A in child with SCADD,who showed normal intelligence and physical development without any clinical symptoms.The mutations of ACADVL gene were c.1349G>A and c.1843C>T in child with VLCADD,who showed acute attack in the neonatal period and recovered after treatment;the child was fed with milk powder rich in medium-chain fatty acids and had normal development during the follow-up.Conclusions:The incidence of FAOD in Chongqing area is relatively high.PCD is the most common type,and the clinical phenotype of VLCADD is serious.After early diagnosis through neonatal screening,standardized treatment and management is followed,most of FAOD children can have good prognosis.