极长链酰基辅酶A脱氢酶缺乏症一例并文献复习

目的探讨中国人群极长链酰基辅酶A脱氢酶缺乏症(VLCADD)的临床特点及基因突变位点情况。方法回顾性分析郑州大学第三附属医院诊治的1例VLCADD患儿的临床诊治经过及基因位点;以"极长链酰基辅酶A脱氢酶缺乏症"为检索词, 检索万方数据库及中国知网数据库, 以"very long chain acyl-coenzyme A dehydrogenase deficiency"和"China"或"Chinese"为检索词, 检索PubMed数据库, 检索以中国人群为研究对象的相关文献, 总结分析VLCADD患者的临床特点, 探讨基因型与表型之间的关系, 以及新生儿筛查对于VLCADD患者预后的影响。结果根据患儿低血糖、肝脏肿大、肝酶升高、血串联质谱C14:1明显升高, 考虑VLCADD, 给予口服左卡尼汀及富含中链脂肪酸配方奶喂养, 患儿病情好转出院, 随访3年10个月, 生长发育正常, 监测血生化指标基本正常。基因检测发现ACADVL基因复合杂合突变, c.692-2₆92-1delAG (splicing)/c.1276G>A (p.A426T)。通过文献检索...     

中、短链酰基辅酶A脱氢酶缺乏症患儿临床特点分析及基因突变研究

中、短链酰基辅酶A 脱氢酶缺乏症属脂肪酸β 氧化障碍疾病,其基因突变可导致中、短链脂肪酸无法进入线粒体进行氧化供能,引起多器官功能异常。本研究对2 例临床表现为低血糖合并代谢性酸中毒的患儿进行血酰基肉碱及尿液有机酸分析,同时对患儿及其父母进行基因突变检测。家系1 患儿,男,3 d,出生后因新生儿窒息、吸奶无力、嗜睡住院治疗。血酰基肉碱谱提示中链酰基肉碱（C6~C10）升高,其中辛酰肉碱（C8）3.52 μmol/L（参考值0.02~0.2 μmol/L）;尿有机酸分析未见明显异常;Sanger 测序发现ACADM 基因7 号外显子已报道纯合突变c.580A>G（p.Asn194Asp）。家系2 患儿,女,3 个月,因咳嗽伴反复发热10 余天住院治疗。血酰基肉碱谱提示血丁酰肉碱（C4）1.66 μmol/L（参考值0.06~0.6 μmol/L）;尿有机酸分析提示乙基丙二酸55.9（参考值0~6.2）;Sanger 测序发现ACADS 基因已报道纯合突变c.625G > A（p.Gly209Ser）。研究结果提示对不明原因代谢性酸中毒及低血糖患儿应进行遗传代谢病筛查,通过家系ACADM、ACADS 基因分析,将有助于中、短链酰基辅酶A 脱氢酶缺乏症的诊断。     

极长链酰基辅酶A脱氢酶缺乏症ACADVL基因新发突变北大核心CSCD

目的探讨1例ACADVL基因突变导致极长链酰基辅酶A脱氢酶缺乏症（VLCADD）的临床特点及基因突变类型,总结导致VLCADD的基因突变类型。方法对内蒙古医科大学附属医院儿科重症监护病房2016年8月收治的1例VLCADD患儿的临床表现及治疗过程进行分析,经患儿监护人同意并签署知情同意书后,行基因（患儿及父母）二代高通量测序分析加PCR测序验证,并以“ACADVL”为检索词,查阅检索中国知网（CNKI）数据库、万方数据库（建库至2016年12月）、PubMed数据库（建库至2016年12月）、在线人类孟德尔遗传数据库（OMIM）及HGMD数据库相关文献,对所发现的突变位点进行分析并总结。结果依据患儿主诉、查体及相关检查化验,提示患儿患有VLCADD,给予13服左卡尼汀及中链脂肪酸饮食1周后复查代谢筛查恢复正常。随访3个月后患儿肝脏明显回缩,为右肋下3cm,剑突下1cm可触及。基因检测发现ACADVL（NM_000018．3）Exon7：c．608C〉T;p．（Pr0203Leu）（杂合）和ACADVL（NM_000018．3）Exonl8：c．1748C〉T;P．（Ser583Leu）（杂合）,为复合杂合突变,致病基因分别来自父母双方。文献检索提示迄今有73种突变类型与VLCADD有关,结合本例患儿的突变类型共有75种突变类型。结论本例VLCADD临床表现特殊,兼有心律失常、肝大和低血糖表现,经过系统治疗可部分控制疾病的发展。基因检测可以明确诊断,上述2种突变可能为VLCADD的新发突变。     

多种酰基辅酶A脱氢酶缺乏症遗传学研究进展

<正>多种酰基辅酶A脱氢酶缺乏症(multiple acyl-CoA dehydrogenasedeficiency,MADD)是由于线粒体氧化呼吸链脱氢产生的电子传递障碍导致脂肪酸、氨基酸及胆碱代谢障碍的一组临床异质性遗传病^[1]。可通过串联质谱分析血酰基肉碱水平对MADD进行新生儿筛查,不同国家和地区新生儿发病率差异较大,美国发病率为1/378 272,德国发病率为1/195 000,     

中链酰基辅酶A脱氢酶缺乏症1例肝脏病理分析及基因检测

目的探讨中链酰基辅酶A脱氢酶缺乏症(MCADD)的诊断和治疗。方法回顾性分析1例MCADD患儿的临床表现、实验室检查以及基因检测结果,并复习相关文献。结果 3岁男性患儿,有一过性低血糖、高氨血症、肝功能损伤;血串联质谱分析提示辛酰肉碱、多种酰基肉碱增高,尿气相色谱质谱分析正常;基因检查示酰基辅酶A脱氢酶基因(acyl-Coenzyme A dehydrogenase,ACADM)c.572GA p.(Trp191*)纯合突变;肝脏病理提示肝细胞轻度损害,炎症程度2级,纤维化程度1级。给予高碳水化合物、高蛋白、低脂肪饮食,积极护肝、降酶、补充肉碱等治疗后患儿肝功能恢复正常。结论血串联质谱分析及基因检测可确诊MCADD,确诊后应积极补充高能量营养物质、肉碱,以预防疾病发作和病情进展。     

一例极长链酰基辅酶A脱氢酶缺乏症患儿串联质谱及基因诊断结果分析

目的熟悉极长链酰基辅酶A脱氢酶缺乏症(very long-chain acyl-CoA dehydrogenase deficiency,VLCADD)的临床表现,加强临床鉴别诊断,增强临床救治能力。方法总结2019年我院遗传中心筛查并于NICU收治的1例VLCADD患儿出生后临床表现、检测结果与随访过程,结合病例及文献进行分析。结果患儿出生后表现为新生儿低血糖症,同时一般实验室检测异常;经串联质谱及基因检测确诊为VLCADD患者,虽经营养支持与对症治疗,但仍未能扭转患儿状况,于诊断1周后死亡。结论VLCADD作为临床上罕见遗传病,鉴别诊断困难。疑似患者应尽早进行串联质谱筛查与分子生物学诊断,VLCADD的诊断时间与分型明显影响患者的预后与生活质量。     

中链酰基辅酶A脱氢酶缺乏症诊治进展

中链酰基辅酶A脱氢酶缺乏症是一种较为常见的线粒体脂肪酸氧化缺陷病。临床表现常见低酮性低血糖、呕吐以及嗜睡、肌无力等。临床表现各异及生化检查不典型可增大诊断难度,容易误诊。由于可以导致急性、致命性低血糖和昏迷发作,若未及时诊治,病死率及遗留后遗症的发生率高,行新生儿遗传代谢病筛查早期确诊并及时治疗,可得到较为满意的结果。     

早发型极长链酰基辅酶A脱氢酶缺乏症3例临床及遗传学分析

目的 探索早发型极长链酰基辅酶A脱氢酶缺乏症(VLCADD)的临床与遗传特征，提高对该疾病的认识。方法 回顾性分析2017年9月至2020年4月在上海交通大学医学院附属新华医院新生儿监护室诊治的3例早发型VLCADD患儿的基因型、临床表型及其预后情况。结果 3例经分子诊断的早发型VLCADD患儿中男2例，女1例，均无阳性家族史。3例患儿均在新生儿期以代谢危象或消化道症状起病。新生儿筛查2例C14:1增高，1例未行筛查。3例患儿均存在ACADVL基因变异，都为复合杂合子，变异来自父母，其中c. 1615 C> T、c. 231-232 insAATG未见报道。1例患儿生后母乳喂养，2日龄呼吸心跳骤停；另2例患儿因新生儿筛查异常，诊断后立即开始富含中链三酰甘油的特殊奶粉喂养，分别于3月龄、4月龄发生猝死。结论 早发型VLCADD为新生儿期、婴儿期潜在猝死性疾病之一，尽管积极开展早期诊断与治疗，但总体预后仍不佳，因此对先证者家系进行产前诊断、避免患儿出生至关重要。     

中链酰基辅酶A脱氢酶缺乏症研究进展

中链酰基辅酶A脱氢酶缺乏症(MCADD)是脂肪酸氧化缺陷病中最常见的一种，其发病率与苯丙酮尿症相当，临床表现主要为低酮性低血糖、呕吐和肌无力。串联质谱方法能检测出无症状的MCADD新生儿血浆中升高的酰基肉碱，兼有敏感度高、特异性高、自动化程度高、高通量等特点。约24％病人第一次发作即导致死亡，32％存活者有心理行为问题或神经功能障碍。若经新生儿疾病筛查得到诊断，现有的预防和治疗效果均较满意。MCADD符合新生儿筛查病种入选标准，部分发达国家已将此病列入新生儿疾病常规筛查项目。     

多种酰基辅酶A脱氢酶缺乏症儿童与成人患者临床特点比较

目的比较儿童和成人多种酰基辅酶A脱氢酶缺乏症(MADD)患者的临床和实验室检查特点。方法对12例儿童和19例成人MADD患者进行常规实验室检查、血酰基肉碱谱及尿有机酸分析。对中国人电子转运黄素蛋白脱氢酶(ETFDH)基因常见突变A84T通过DNA测序方法进行筛检。结果儿童MADD患者临床表现高度异质,可表现为肌无力、肝大、低酮性低血糖、肥厚性心肌病或脑发育不良及脱髓鞘病变;而成人患者均以肌无力起病。成人和儿童MADD有肝酶和CK升高,血多种酰基肉碱升高,多数伴有二羧酸尿。儿童组3例死亡,成人组全部存活。存活患者的症状和生化指标治疗后好转或正常。A84T突变在儿童和成人患者的发生率分别为20.8%(5/24)和21%(8/38)。结论儿童与成人MADD患者的临床表现和预后存在差异,成人患者预后好;A84T突变可能与轻型相关。[临床儿科杂志,2012,30(5):446-449]     

Pitfalls of neonatal screening for very-long-chain acyl-CoA dehydrogenase deficiency using tandem mass spectrometry

Neonatal screening programs for very-long-chain acyl-CoA dehydrogenase deficiency (VLCADD) have recently been implemented. We report 2 newborns with elevated C14:1-carnitine levels on day 3 of life and normal levels on days 5 to 7. Enzyme and molecular analyses confirmed VLCADD in the first patient and heterozygosity in the second patient. We conclude that the diagnosis of VLCADD can be missed by acylcarnitine analysis during anabolic conditions. An increased C14:1-carnitine level can also occur in heterozygous individuals. Elevated C14:1-carnitine level on neonatal screening warrants further diagnostic workup even if a repeat sample demonstrates normal acylcarnitine levels.     

Influence of valproic acid on the expression of various acyl-CoA dehydrogenases in rats

BACKGROUND: Valproic acid (2-propyl-N-pentanoic acid, VPA) causes severe hepatic dysfunction, similar to Reye's syndrome, in a small number of patients. An enhanced excretion of dicarboxylic acids by patients indicates an interference with mitochondrial beta-oxidation. We investigated the expression of various acyl-coenzyme A (acyl-CoA) dehydrogenases (ACD), which catalyze the first step of beta-oxidation in VPA-treated rats. METHODS: The control group received normal saline and the experimental group received VPA (500 mg/kg per day) by intraperitoneal injections for 7 days. Various clinical chemistry parameters in rat blood and free and total carnitine levels in plasma and tissue were determined. Mitochondria were isolated from rat liver and heart and the relative amount of each ACD protein was determined by immunoblot analysis. Total RNA was prepared from various tissues and the mRNA levels for various ACD were measured by slot-blot hybridization analysis using respective cDNA probes. RESULTS: Administration of VPA to rats caused various metabolic effects including hypoglycemia, hyperammonemia and decreased beta-hydroxybutyrate concentration. Free carnitine levels in plasma and heart were also decreased. Enzyme activities of various acyl-CoA dehydrogenases, which are involved in fatty acid oxidation, decreased moderately in heart (57-79%), and slightly in liver (78-95%). The most prominent effects were observed in mRNA levels involved in fatty acid oxidation (short-, medium- and long-chain acyl-CoA dehydrogenase). Each mRNA increased in the liver, kidney, skeletal muscle and heart to varying degrees when rats were fed ad libitum. The increase of short- and medium- chain acyl-CoA dehydrogenase mRNA in the heart were particularly large. However, 3 day starvation strongly inhibited expression of ACD in VPA-treated rats. There was an apparent decrease in the amount of ACD mRNA and proteins in VPA-treated liver. CONCLUSIONS: Valproic acid causes enhanced expression of fatty ACD mRNA, especially in the heart, by a feedback mechanism related to inhibition of beta-oxidation in rats fed ad libitum. However, it impairs the expression of ACD in the liver when there is a drastic change in nutritional state.     

Positive newborn screen in a normal infant of a mother with asymptomatic very long-chain Acyl-CoA dehydrogenase deficiency

A neonate with elevated tetradecenoylcarnitine (C14:1) on the newborn screen was evaluated for possible very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) and found to be a carrier. However, his symptom-free mother was subsequently diagnosed with VLCADD. This documents maternal VLCADD causing a positive newborn screening result in an offspring.     

Retrospective diagnosis of medium chain acyl-CoA dehydrogenase deficiency

Abstract A male infant is reported who died suddenly and who at post-mortem had pathological evidence suggestive of a genetic defect of fatty acid β-oxidation. A specific diagnosis could not be made enzymatically because of unavailability of suitable tissue for assay. The diagnosis of medium chain acyl-CoA dehydrogenase (MCAD) deficiency was made by specific mutation analysis using the polymerase chain reaction and DNA extracted from the newborn screening card of this infant. This powerful new molecular diagnostic technique should prove to be of use in similar circumstances.     

Milder childhood form of very long-chain acyl-CoA dehydrogenase deficiency in a 6-year-old Japanese boy

We investigated the clinical and biochemical characteristics of a 6-year-old Japanese boy with very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. He had hypoketotic hypoglycaemia, exercise- and fasting-induced lethargy, hepatomegaly and cardiomegaly. Significant laboratory findings included elevated plasma levels of creatine phosphokinase and acyl-carnitine and a fatty liver at biopsy suggesting a diagnosis of VLCAD deficiency. Conclusion The diagnosis of very long-chain acyl-CoA dehydrogenase deficiency was supported by the results of acyl-CoA dehydrogenase activity for C₈ and C₁₆ fatty acids in skin fibroblasts from the patient. Treatment with medium chain triglycerides and l-carnitine in the diet improved his hepatomegaly and cardiomegaly. Received: 17 April 2000 / Accepted: 5 July 2000     

Carrier detection in X-linked adrenoleukodystrophy by determination of very long chain fatty acid levels and by linkage analysis

Diagnosis of X-linked adrenoleukodystrophy is based upon demonstration of high levels of very long chain fatty acids. More recently, in addition to biochemical analysis, closely linked DNA probe St14 has been used for prenatal diagnosis in informative families. Identification of heterozygotes is particularly important, both in order to specifically address only carrier females to prenatal diagnosis, and because appropriate dietary therapy is now available to treat those heterozygotes presenting with neurological symptoms. We report two pedigrees in which carrier detection was performed by a combination of biochemical and molecular genetic analysis. Such approach should allow extremely high accuracy in carrier detection.     

Frequencies of inherited organic acidurias and disorders of mitochondrial fatty acid transport and oxidation in Germany

The lack of epidemiological data on the frequency and/or burden of organic acidurias (OA) and mitochondrial fatty acid transport and oxidation disorders (mtFATOD) is one reason for hesitation to expand newborn screening (NBS) by tandem mass spectrometry (MS-MS). From 1999 to 2000, the frequency of ten potentially treatable OA and mtFATOD was assessed by active nation-wide surveillance on cases presenting with clinical symptoms using the German Paediatric Surveillance Unit (ESPED) system. Case ascertainment was complemented by a second independent source: 3-monthly inquiries in the metabolic laboratories performing secondary selected screening for OA and mtFATOD. Frequency estimates for clinically symptomatic cases older than 7 days in a birth cohort of 844,575 conventionally screened children was compared to the frequency found in a cohort of 382,247 screened by MS-MS in Bavaria and Baden-Württemberg. The overall frequency of the ten conditions considered was 1:8,000 (95% CI 1:11,000–1:6,000) by MS-MS as compared to 1:23,000 (95% CI 1:36,000–1:17,000) in symptomatic cases presenting mainly with metabolic crisis. The contributions of medium-chain acyl-CoA dehydrogenase deficiency (MCADD), other mtFATOD and OA were 29, 4 and 13 among the 46 cases identified by MS-MS, and 19, 1 and 13 among the 33 clinically symptomatic cases, respectively. Acute metabolic crisis, with a lethal outcome in four patients, was reported for 22/33 clinically symptomatic cases. No clinically symptomatic cases were reported from cohorts with screened by MS-MS. Conclusion: ten potentially treatable organic acidurias and mitochondrial fatty acid transport and oxidations disorders were more common than phenylketonuria with organic acidurias accounting for 28% of the cases detected by newborn screening and 39% of the cases identified on high risk screening. These conditions were related to considerable morbidity and mortality. Considerations for their inclusion in expanded newborn screening programmes might be warranted.Abbreviations ESPED Erhebungseinheit für seltene pädiatrische Erkrankungen in Deutschland (German Paediatric Surveillance Unit) - MCADD medium-chain acyl-CoA dehydrogenase deficiency - MS-MS tandem mass spectrometry - mtFATOD mitochondrial fatty acid transport and oxidation disorders - NBS newborn screening - OA organic acidurias     

Clinical features and mutations in seven Chinese patients with very long chain acyl-CoA dehydrogenase deficiency

Background

Very long chain acyl-CoA dehydrogenase deficiency (VLCADD) is an inherited metabolic disease caused by deleterious mutations in the ACADVL gene that encodes very long chain acyl-CoA dehydrogenase (VLCAD), and which can present as cardiomyopathy in neonates, as hypoketotic hypoglycemia in infancy, and as myopathy in late-onset patients. Although many ACADVL mutations have been described, no prevalent mutations in the ACADVL gene have been associated with VLCADD. Herein, we report the clinical course of the disease and explore the genetic mutation spectrum in seven Chinese patients with VLCADD.

Methods

Seven Chinese patients, from newborn to 17 years old, were included in this study. Tandem mass spectrometry was performed to screen for VLCAD deficiency. All exons and flanking introns of the ACADVL gene were analyzed using polymerase chain reaction and direct sequencing. Online analysis tools were used to predict the impact of novel mutations.

Results

All cases had elevated serum levels of tetradecanoylcarnitine (C14:1) which is the characteristic biomarker for VLCADD. The phenotype of VLCADD is heterogeneous. Two patients were hospitalized for hypoactivity and hypoglycemia shortly after birth. Three patients showed hepatomegaly and hypoglycemia in infancy. The other two adolescent patients showed initial manifestations of exercise intolerance or rhabdomyolysis. Three of the patients died at the age of 6–8 months. Eleven different mutations in the ACADVL gene in the 7 patients were identified, including seven reported mutations (p.S22X, p.W427X, p.A213T, p.G222R, p.R450H, c.296-297delCA, c.1605+1G>T) and four novel mutations (p.S72F, p.Q100X, p.M437T, p.D466Y). The p.R450H and p.D466Y (14.28%, 2/14 alleles) mutations were identified in two alleles respectively.

Conclusions

The clinical manifestations were heterog-eneous and ACADVL gene mutations were heterozygous in the seven VLCADD Chinese patients. R450H may be a relatively common mutation in Asian populations. The genotype and phenotype had a certain correlation in our patients.