50例新生儿原发性肉碱缺乏症的基因谱及临床特征分析

发布时间：2018-02-23 07:51

本文关键词： 原发性肉碱缺乏症新生儿疾病筛查串联质谱基因治疗预后　出处：《浙江大学》2015年博士论文　论文类型：学位论文

【摘要】：研究目的：探讨新生儿原发性肉碱缺乏症(PCD)的患病率、基因谱及临床特征,为早期诊断提供依据。研究方法：采用串联质谱分析技术,对2009年1月至2014年12月在浙江大学医学院附属儿童医院新生儿疾病筛查中心的新生儿进行疾病筛查,收集所有经诊治、随访的PCD确诊病例和致病基因携带病例,分别记录其性别、孕周、出生体重、采血日龄、初筛时血浆游离肉碱(CO)水平、用药剂量、CO水平恢复正常所需时间、家族史、临床表现、相关体格检查和实验室检查、心电图及影像学表现、基因检测结果、随访时间及预后,以及母亲年龄和血浆CO水平。研究结果： 1.6年间共筛查新生儿1,119,198例,发现PCD确诊病例共50例,患病率约1：22,384；其中足月儿48例、早产儿2例；男女比1：1.38,平均孕周38+周,平均出生体重3270g,平均采血日龄3.7天,母亲平均年龄28.1岁。致病基因携带病例共27例,均为足月儿,男女比例1：1.07,平均孕周39+周,平均出生体重3300g,平均采血日龄3.6天,母亲平均年龄28.5岁。 2.确诊组检测基因33例,共检测到23种、67个突变位点,大多数集中于外显子1、4、8。共发现11种已知致病突变位点,分别为c.1400CG(p.S467C). c.760CT(p.R254X)、c.51CG(p.F17L)、c.865CT(p.R289X)、c.1195C T(p.R399W)、c.338GA(p.C113Y)、c.845GA(p.R282Q)、c.428CT(p.P143L)、 c.1433CT(p.P478L)cc.505CT(p.R169W)、c.652+1GA,和12种新发突变位点,c.308TG(p.V103G)、c.1505CA(p.T502K)、c.1445AG(p.Y482C). c.538CG(p.Q180E)、c.1427TC(p.L476P)、c.40TA(p.W14R)、c.1362T G(p.Y454X)、C.1252CT(p.Q418X)、c.42GA(p.W14X)、c.498-2AG、 c.507de1G(p.R169RfsX5)、c.252_265dup14(p.I89TfsX46)。其中,最常见的突变位点为c.1400CG(p.S467C),出现频率约34.3%；其次是c.760CT(p.R254X)(19.4%)和c.51CG(p.F17L)(11.9%)。 3.携带组检测基因6例,母亲中共检测到4种、12个突变位点,包括1种未知突变位点c.497+1GT和3种已知致病突变位点c.1400CG(p.S467C)、c.760CT(p.R254X)及c.51CG(p.F17L);最常见突变位点为c.1400CG(p.S467C),出现频率75%。6例婴儿中的4例携带c.1400CG(p.S467C)突变,2例分别携带c.51CG(p.F17L)、c.760CT(p.R254X)突变；其中c.1400CG(p.S467C)突变仍为最常见突变位点,出现频率约66.7%。 4.初次筛查(以下简称初筛)时,确诊组患儿的平均血浆CO水平为[(7.70±2.70)μmol/L],携带组为[(6.43±2.33)μmol/L],均低于正常,但组间无显著差异(p0.01)。确诊组用药前的血浆CO水平呈下降趋势,而携带组则呈上升趋势,二者存在显著差异(p=0.000)。恢复时间上,确诊组(中位数32天)显著长于携带组(中位数26天)(p=0.000)。 5.确诊组患儿除8例失访、2例中断治疗外,均无任何PCD相关症状；16例携带组母亲有腿酸、易疲劳、低血糖发作等症状。 6.确诊组有4例患儿同胞行基因检测,结果2例为PCD患者,2例为携带者。 7.除失访者外,确诊组平均随访时间为19.7个月,遵医嘱服药、定期复查者预后良好。2例自行停药患儿1例猝死,1例感染后瑞氏综合征样脑病发作。 8.纯合突变病例在初筛血浆CO水平、恢复时间、临床表现方面与杂合突变病例不存在显著差异(p0.01)。结论： 1.原发性肉碱缺乏症为最常见的脂肪酸代谢异常疾病之一,本省新生儿患病率高于目前文献报道。 2.大多数突变集中于外显子1、4、8,占所有突变的77.6%。其中,c.1400C G(p.S467C)、c.760CT(p.R254X)、c.51CG(p.F17L)突变是新生儿PCD最常见的基因突变位点,约占所有突变的65.6%(依次为34.3%、19.4%、11.9%)。c.1400CG(p.S467C)突变是母亲PCD患者的最常见突变位点(75%)。 3.单凭新生儿初筛血浆CO水平无法区分PCD确诊者与携带者；但母亲血浆CO水平正常或略低于正常、用药前血浆C0呈下降趋势、用药后恢复时间长等因素,均是诊断PCD的有力依据。 4.早期发现、规范治疗、长期随访者预后良好；中止治疗可诱发严重临床事件。 5.未发现新生儿PCD患者基因型与表现型的相关性。
[Abstract]:The purpose of the study is:
To explore the prevalence, gene spectrum and clinical characteristics of neonatal primary carnitine deficiency (PCD), and to provide a basis for early diagnosis.
Research methods:
The analysis of tandem mass spectrometry, on January 2009 to December 2014 at the children's Hospital Affiliated to Medical College of Zhejiang University neonatal screening center of neonatal disease screening, collect all confirmed cases of PCD after treatment, and follow-up of pathogenic gene carrying cases were recorded the sex, gestational age, birth weight, blood age, screening of plasma free carnitine (CO) the level of dose, CO levels returned to normal time, family history, clinical manifestation, physical examination and laboratory examination and imaging manifestations, ECG, gene analysis, follow-up and prognosis, and maternal age and the level of plasma CO.
The results of the study:
Between 1.6 and 1119198 neonates were screened and found PCD cases were 50 cases, the prevalence rate of about 1:22384; 48 cases of full-term infants, 2 cases of premature infants; and the ratio of 1:1.38, the average gestational age of 38+ weeks, the average birth weight of 3270g, the average was 3.7 days, with an average age of 28.1 years. The mother of pathogenic gene carrying case a total of 27 cases were full-term infants, male to female ratio was 1:1.07, the average gestational age of 39+ weeks, the average birth weight of 3300g, the average was 3.6 days, the mother with an average age of 28.5.
2. detection of gene diagnosis group 33 cases were detected 23, 67 mutations, most concentrated in exons 1,4,8. were found in 11 known pathogenic mutations, respectively. C.1400CG (p.S467C) c.760CT (p.R254X), c.51CG (p.F17L), c.865CT (p.R289X), c.1195C T (p.R399W), c.338GA (p.C113Y), c.845GA (p.R282Q), c.428CT (p.P143L), c.1433CT (p.P478L) cc.505CT (p.R169W), c.652+1GA, and 12 kinds of new mutations, c.308TG (p.V103G), c.1505CA (p.T502K), c.1445AG (p.Y482C). C.538CG (p.Q180E), c.1427TC (p.L476P), c.40TA (p.W14R), c.1362T G (p.Y454X), C.1252CT (p.Q418X), c.42GA (p.W14X), c.498-2AG, c.507de1G (p.R169RfsX5), c.252_265dup14 (p.I89TfsX46). Among them, the most common mutation sites of c.1400CG (p.S467C), the frequency of about 34.3%; followed by c.760CT (p.R254X) (19.4%) and c.51CG (p.F17L) (11.9%).
The 3. group carrying gene detection in 6 cases, mothers were detected 4, 12 mutations, including 1 novel mutations of c.497+1GT and 3 known pathogenic mutations of c.1400CG (p.S467C), c.760CT (p.R254X) and c.51CG (p.F17L); the most common mutations of c.1400CG (p.S467C), the frequency of 75%.6 infants in 4 cases with c.1400CG (p.S467C) mutation, 2 cases were with c.51CG (p.F17L), c.760CT (p.R254X) c.1400CG (p.S467C) mutation; mutation is still the most common mutations, the frequency of about 66.7%.
4. the initial screening (hereinafter referred to as screening), the mean plasma CO level diagnosis groups for [(7.70 + 2.70) mol/L], carrying Group [(6.43 + 2.33) mol/L], were lower than normal, but no significant difference between groups (P0.01). Diagnosis group before treatment plasma CO level was the decline, increased while carrying a group, there are significant differences between the two (p=0.000). The recovery time, diagnosis group (median 32 days) was significantly longer than that of carrier group (median 26 days) (p=0.000).
5. patients in the 5. confirmed group had 8 cases of loss of visit, 2 cases of interruption treatment, no symptoms related to any other, 16 cases of the mother with leg acid, fatigue, hypoglycemia and other symptoms.
6. of the 6. confirmed patients were detected in 4 of their siblings, the results were 2 cases and 2 were carriers.
7. in addition to those who lost the interview, the average time of follow-up in the diagnosis group was 19.7 months. The patients who took the medicine regularly and regularly reviewed had good prognosis. In the.2 group, 1 cases died suddenly, and 1 cases had Rees syndrome encephalopathy after infection.
8. homozygous mutations were not significantly different from heterozygous mutations in the initial screening of plasma CO level, recovery time and clinical manifestations (P0.01).
Conclusion:
1. primary carnitine deficiency is one of the most common disorders of fatty acid metabolism. The prevalence rate of newborn infants in this province is higher than that of the present literature.
2. most of the mutations in exon 1,4,8, accounting for all the mutations of 77.6%., c.1400C G (p.S467C), c.760CT (p.R254X), c.51CG (p.F17L) mutation is the most common neonatal PCD gene mutations, accounting for about 65.6% of all mutations (were 34.3%, 19.4%, 11.9%).C.1400CG (p.S467C) mutation mother PCD were the most common mutations (75%).
3., the CO level of newborn infants was not able to distinguish the PCD from the carriers, but the plasma CO level was normal or slightly below the normal level. The plasma C0 decreased before medication and the recovery time was long after treatment. All these factors were the strong basis for the diagnosis of PCD.
4. early detection, standardized treatment, long-term follow-up patients have good prognosis, discontinuation of treatment can induce serious clinical events.
5. the correlation between genotypes and phenotype was not found in neonatal PCD patients.

【学位授予单位】：浙江大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：R722.1

【共引文献】