Very-long chain acyl-coA dehydrogenase deficiency: report of a Chinese pedigree and a literature review / 中华医学遗传学杂志

OBJECTIVE@#To explore the correlation between clinical classification and genotype and prognosis among Chinese children with Very-long chain acyl-CoA dehydrogenase deficiency (VLCADD).@*METHODS@#A Chinese pedigree affected with VLCADD admitted at the First People's Hospital of Yunnan Province in February 2019 was selected as the study subject. The characteristics of disease onset, diagnosis and treatment and prognosis were retrospectively analyzed. Relevant literature was also systematically searched and reviewed.@*RESULTS@#The proband, a 1-year-old boy, had the clinical manifestations of frequently vomiting, hypoglycemia, abnormal liver function and myocardial enzymes. Tandem mass spectrometry screening showed significantly elevated C14, C14:1, C16:1, C16:2, C18 and C14/C8. Genetic testing revealed that he has harbored compound heterozygous variants of the ACADVL gene, namely c.664G>A (p.G222R) and c.1345G>A (p.E449K), which were respectively derived from his father and mother. The child was diagnosed with VLCADD cardiomyopathy type and deceased 2 weeks later. Literature review has identified 60 Chinese children with VLCADD. The clinical classifications were mainly cardiomyopathy type and liver disease type, which accounted for 73.3% (43/60). The combination of ACADVL gene variants were correlated with the clinical classifications of VLCAD. Children with one or two loss-of-function (LOF) mutations showed more severe clinical manifestation and a higher mortality. Cardiomyopathy type had the poorest prognosis, with a mortality rate of 76.9% (20/26). C14:1 may be used as an indicator for the diagnosis of VLCADD, but cannot be used for clinical subtyping and prognosis evaluation. The c.1349G>A (p.R450H) variant had the highest frequency among the Chinese patients, accounting for 10.8% (13/120).@*CONCLUSION@#The clinical classifications of VLCADD are strongly correlated with the prognosis, and LOF mutations are more common in those with severe clinical manifestations. c.1349G>A (p.R450H) may be the most common variant among the Chinese patients, and early screening and diagnosis can greatly improve the prognosis of patients.

Analysis of clinical characteristics and ACADM gene variants in four children with Medium chain acyl-CoA dehydrogenase deficiency / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical and genetic characteristics of four patients with medium-chain acyl-CoA dehydrogenase deficiency (MCADD).@*METHODS@#Four children who had presented at the Children's Hospital Affiliated to Zhengzhou University between August 2019 and August 2021 were selected as the study subjects. Clinical data of the children were collected. The children were subjected to whole exome sequencing (WES).@*RESULTS@#All of the four children were diagnosed with MCADD. Blood amino acid and ester acyl carnitine spectrum test showed that the concentration of octanoyl carnitine (C8) was significantly increased. The main clinical manifestations included poor mental response (3 cases), intermittent diarrhea with abdominal pain (1 case), vomiting (1 case), increased transaminase (3 cases), and metabolic acidosis (2 cases). Five variants were identified by genetic testing, among which c.341A>G (p.Y114C) was unreported previously. Three were missense variants, one was frameshift variant and one was splicing variant.@*CONCLUSION@#The clinical heterogeneity of MCADD is obvious, and the severity of the disease may vary. WES can assist with the diagnosis. Delineation of the clinical symptoms and genetic characteristics of the disease can facilitate early diagnosis and treatment of the disease.

Tandem mass spectrometry and genetic variant analysis of four neonates with very long chain acyl-coenzyme A dehydrogenase deficiency / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical features and genetic variants in four neonates with very long chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency.@*METHODS@#Neonates with a tetradecenoylcarnitine (C14:1) concentration at above 0.4 μmol/L in newborn screening were recalled for re-testing. Four neonates were diagnosed with VLCAD deficiency by MS-MS and genetic testing, and their clinical features and genotypes were analyzed.@*RESULTS@#All cases had elevated blood C14:1, and the values of first recalls were all lower than the initial test. In 2 cases, the C14:1 had dropped to the normal range. 1 case has remained at above 1 μmol/L after the reduction, and the remainder one case was slightly decreased. In total eight variants of the ADACVL genes were detected among the four neonates, which included 5 missense variants and 3 novel variants (p.Met344Val, p.Ala416Val, c.1077+6T>A). No neonate showed salient clinical manifestations.@*CONCLUSION@#Above findings have enriched the spectrum of ADACVL gene mutations and provided a valuable reference for the screening and diagnosis of VLCAD deficiency.

Síndrome de Pearson en un niño trasplantado debido a anemia de Diamond-Blackfan / Pearson syndrome in a child transplanted for Diamond-Blackfan anemia

El síndrome de Pearson (SP) comparte varias características con la anemia de Diamond-Blackfan (ADB), incluida la anemia grave de inicio temprano, por lo que es importante hacer un diagnóstico diferencial. El diagnóstico diferencial de la ADB y el SP es fundamental, ya que los pacientes con ADB podrían res-ponder al tratamiento con corticoesteroides, presentar remisión o beneficiarse del trasplante de células madre hematopoyéti-cas (TCMH). Sin embargo, los pacientes con SP tienen un pronós-tico diferente, con un riesgo muy elevado de acidosis, problemas metabólicos y disfunción pancreática, y una expectativa de vida menor en comparación con aquellos con ADB. En este artículo, presentamos el caso de un paciente sometido a TCMH para la ADB, pero que luego fue diagnosticado con SP tras desarrollar algunas complicaciones.

Pearson syndrome (PS), shares a number of overlapping features with Diamond-Blackfan anemia (DBA), including early onset of severe anemia, making differential diagnosis important. Differential diagnosis of DBA and PS is critical, since those with DBA may respond to treatment with steroids, may undergo remission, or may benefit from hematopoietic stem cell transplantation (HSCT). However, patients with PS have a different prognosis, with a very high risk of developing acidosis, metabolic problems, and pancreatic dysfunction, and a shorter life expectancy than those with DBA. Here we present a patient who underwent HSCT for DBA but was subsequently diagnosed with PS after developing some complications

Analysis of a child with carnitine palmitoyl transferase 1A deficiency due to variant of CPT1A gene / 中华医学遗传学杂志

OBJECTIVE@#To report on the clinical, metabolic and genetic characteristics of a child with carnitine palmitoyl transferase 1A (CPT1A) deficiency.@*METHODS@#Clinical data and the level of acylcarnitine for a child who initially presented as epilepsy were analyzed. Genomic DNA was extracted from peripheral blood samples of the child and her parents and subjected to next-generation sequencing (NGS).@*RESULTS@#Mass spectrometry of blood acylcarnitine indicated increased carnitine 0 (C0) and significantly increased C0/ (C16+C18). DNA sequencing revealed that the child has carried compound heterozygous variants of the CPT1A gene, namely c.1846G>A and c.2201T>C, which were respectively inherited from her mother and father.@*CONCLUSION@#CPT1A presenting initially as epilepsy was unreported previously. Analysis of blood acylcarnitine C0 and C0/ (C16 + C18) ratio and NGS are necessary for the identification and diagnosis of CPT1A deficiency. The c.1846G>A and c.2201T>C variants of the CPT1A gene probably underlay the disease in this child. Above finding has also enriched the spectrum of CPT1A gene variants.

Activated mTOR signaling pathway in myofibers with inherited metabolic defect might be an evidence for mTOR inhibition therapies / 中华医学杂志(英文版)

BACKGROUND@#Abnormally activated mechanistic target of rapamycin (mTOR) pathway has been reported in several model animals with inherited metabolic myopathies (IMMs). However, the profiles of mTOR pathway in skeletal muscles from patients are still unknown. This study aimed to analyze the activity of mTOR pathway in IMMs muscles.@*METHODS@#We collected muscle samples from 25 patients with mitochondrial myopathy (MM), lipid storage disease (LSD) or Pompe disease (PD). To evaluate the activity of mTOR pathway in muscle specimens, phosphorylation of S6 ribosomal protein (p-S6) and p70S6 kinase (p-p70S6K) were analyzed by Western blotting and immunohistochemistry.@*RESULTS@#Western blotting results showed that p-p70S6K/p70S6K in muscles from LSD and MM was up-regulated when compared with normal controls (NC) (NC vs. LSD, U = 2.000, P = 0.024; NC vs. MM: U = 6.000, P = 0.043). Likewise, p-S6/S6 was also up-regulated in muscles from all three subgroups of IMMs (NC vs. LSD, U = 0.000, P = 0.006; NC vs. PD, U = 0.000, P = 0.006; NC vs. MM, U = 1.000, P = 0.007). Immunohistochemical study revealed that p-S6 was mainly expressed in fibers with metabolic defect. In MM muscles, most p-S6 positive fibers showed cytochrome C oxidase (COX) deficiency (U = 5.000, P = 0.001). In LSD and PD muscles, p-S6 was mainly overexpressed in fibers with intramuscular vacuoles containing lipid droplets (U = 0.000, P = 0.002) or basophilic materials (U = 0.000, P = 0.002).@*CONCLUSION@#The mTOR pathway might be activated in myofibers with various metabolic defects, which might provide evidence for mTOR inhibition therapy in human IMMs.

Analysis of ACADVL gene variations among nine neonates with very long chain acyl-coA dehydrogenase deficiency / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical features and variations of ACADVL gene in 9 neonates with very long chain acyl-coenzyme A dehydrogenase deficiency (VLCADD).@*METHODS@#VLCADD was suspected based on the results of neonatal screening by tandem mass spectrometry (MS-MS), with tetradecenoylcarnitine ± tetradecenoylcarnitine/octanoylcarnitine (C14: 1 ± C14: 1/C8) as the mark indexes. Infants with positive outcome were confirmed by sequencing of the ACADVL gene.@*RESULTS@#Among 9 VLCADD cases, one case lost during follow-up, the observed phenotypes comprised 2 with severe early-onset form, 1 with hepatic form and 5 with late-onset form. Optimal outcome was acquired for all patients except the 2 early-onset cases. In total 16 ACADVL variations were detected among the 9 infants, which included 8 novel variations (c.96-105del GCCCGGCCCT, c.541C>T, c.863T>G, c.878+1G>C, c.895A>G, c.1238T>C, c.1276G>A, and c.1505T>A) and 11 missense variations. There were 9 genotypic combinations, including 1 homozygote and 8 compound heterozygotes. Except for two patients carrying null variations, all had a good outcome.@*CONCLUSION@#VLCADD is relatively rare in southern China, for which late-onset form is common. Carriers of null variations of the ACADVL gene may have relatively poorer clinical outcome. Above results will provide valuable information for the diagnosis and management of VLCADD.

Analysis of ETFDH gene variation in a Chinese family affected with lipid storage myopathy / 中华医学遗传学杂志

OBJECTIVE@#To detect potential variation in an ethnic Han Chinese family affected with late-onset lipid storage myopathy.@*METHODS@#Next generation sequencing (NGS) was used to screen disease-related genes in the proband. Suspected mutation was validated with PCR and Sanger sequencing in two patients, their father, and 100 healthy controls.@*RESULTS@#Heterozygous c.770A>G (p.Tyr257Cys) and c.1395dupT (p.Gly466Tryfs) mutation were detected in the two patients. Their father was found to be heterozygous for the c.770A>G (p.Tyr257Cys) mutation, while the c.1395dupT (p.Gly466Tryfs) variation was not reported previously and not found among the healthy controls.@*CONCLUSION@#Mutations of the ETFDH gene probably underlie the pathogenesis in this family. The novel c.1395dupT (p.Gly466Tryfs) has enriched the mutation spectrum of EDFDH gene.

Tandem mass spectrometry analysis and genetic diagnosis of neonates with fatty acid oxidation disorders in central and northern regions of Guangxi / 中华医学遗传学杂志

OBJECTIVE@#To determine the incidence and mutational types of fatty acid oxidation disorders (FAOD) in central-northern region of Guangxi.@*METHODS@#A total of 62 953 neonates were screened for FAOD during December 2012 and December 2017. Acyl-carnitine profiling of neonatal blood sample was performed by tandem mass spectrometry using dry blood spots on a filter paper. The diagnosis of FAOD was confirmed by organic acid profiling of urea and genetic testing.@*RESULTS@#Eighteen cases of FAOD were diagnosed among the 62 953 neonates. Among these, primary carnitine deficiency (PCD) was the most common type (n=13), which was followed by short-chain acyl-CoA dehydrogenase deficiency (SCADD) (n=2), medium-chain acyl-CoA dehydrogenase deficiency (MCADD) (n=1), multiple acyl-CoA dehydrogenase deficiency (MADD) (n=1), and carnitine palmitoyltransferase II deficiency (CPT II D) (n=1). Genetic testing has revealed two previously unreported variants, i.e., c.337G to A (p.Gly113Arg) of ACADS gene and c.737G TO T (p.Gly246Val) of ETFA gene.@*CONCLUSION@#PCD is the most common FAOD in central-northern Guangxi. Tandem mass spectrometry combined with genetic testing may facilitate early diagnosis of FAOD.

Medium-chain acyl-CoA dehydrogenase deficiency: neonatal screening and follow-uP / 中国当代儿科杂志

OBJECTIVE@#To investigate the epidemiological characteristics, phenotype, genotype, and prognosis of medium-chain acyl-CoA dehydrogenase deficiency (MCADD) in the Chinese population.@*METHODS@#A retrospective analysis was performed for the clinical data of the neonates who underwent screening with high-performance liquid chromatography-tandem mass spectrometry from January 2009 to June 2018 and were diagnosed with MCADD by gene detection.@*RESULTS@#A total of 2 674 835 neonates underwent neonatal screening, among whom 12 were diagnosed with MCADD. Gene detection was performed for 10 neonates with MCADD and found 13 mutation types at 16 mutation sites of the ACADM gene, among which there were 7 reported mutations (p.T150Rfs*4, p.M1V, p.R206C, p.R294T, p.G310R, p.M328V, and p.G362E), 5 novel mutations (p.N194D, p.A324P, p.N366S, c.118+3A>G, and c.387+1del G), and 1 exon 11 deletion; p.T150Rfs*4 was the most common mutation (4/16). The detection rate of mutation sites in the ACADM gene was 80%. No phenotype-genotype correlation was observed. Dietary guidance and symptomatic treatment were given after confirmed diagnosis. No acute metabolic imbalance was observed within 4-82 months of follow-up. All neonates had good prognosis except one who had brain dysplasia.@*CONCLUSIONS@#MCADD is relatively rare in southern China, and p.T150Rfs*4 is a common mutation in the Chinese population. Cases with positive screening results should be evaluated by octanoylcarnitine C8 value and gene detection.

Clinical features and genetic analysis of a case with carnitine palmitoyltransferase 1A deficiency / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the clinical and molecular features of a child with carnitine palmitoyltransferase 1A (CPT1A) deficiency.</p><p><b>METHODS</b>Clinical data of the child was collected. Blood acylcarnitine was determined with tandem mass spectrometry. DNA was extracted from the child and his parents. All exons and flanking regions of the CPT1A gene were analyzed by PCR and Sanger sequencing.</p><p><b>RESULTS</b>Analysis showed that the patient carried compound heterozygous mutations c.1787T>C and c.2201T>C of the CPT1A gene, which derived his father and mother, respectively. Both mutations were verified as novel through the retrieval of dbSNP, HGMD and 1000 genome databases. Bioinformatic analysis suggested that the mutations can affect protein function.</p><p><b>CONCLUSION</b>Acyl carnitine analysis has been the main method for the diagnosis of CPT1A deficiency. The c.1787T>C and c.2201T>C mutations of the CPT1A gene probably underlie the disease in this patient. Gene testing can provide important clues for genetic counseling and prenatal diagnosis.</p>

An analysis of clinical characteristics and gene mutation in two patients with medium- and short-chain acyl-CoA dehydrogenase deficiency / 中国当代儿科杂志

Medium- and short-chain acyl-CoA dehydrogenase deficiency is a disorder of fatty acid β-oxidation. Gene mutation prevents medium- and short-chain fatty acids from entry into mitochondria for oxidation, which leads to multiple organ dysfunction. In this study, serum acylcarnitines and the organic acid profile in urea were analyzed in two children whose clinical symptoms were hypoglycemia and metabolic acidosis. Moreover, gene mutations in the two children and their parents were evaluated. One of the patients was a 3-day-old male who was admitted to the hospital due to neonatal asphyxia, sucking weakness, and sleepiness. The serum acylcarnitine profile showed increases in medium-chain acylcarnitines (C6-C10), particularly in C8, which showed a concentration of 3.52 μmol/L (reference value: 0.02-0.2 μmol/L). The analysis of organic acids in urea gave a normal result. Sanger sequencing revealed a reported c.580A>G (p.Asn194Asp) homozygous mutation at exon 7 of the ACADM gene. The other patient was a 3-month-old female who was admitted to the hospital due to cough and recurrent fever for around 10 days. The serum acylcarnitine profile showed an increase in serum C4 level, which was 1.66 μmol/L (reference value: 0.06-0.6 μmol/L). The analysis of organic acids in urea showed an increase in the level of ethyl malonic acid, which was 55.9 (reference value: 0-6.2). Sanger sequencing revealed a reported c.625G>A (p.Gly209Ser) homozygous mutation in the ACADS gene. This study indicates that screening tests for genetic metabolic diseases are recommended for children who have unexplained metabolic acidosis and hypoglycemia. Genetic analyses of the ACADM and ACADS genes are helpful for the diagnosis of medium- and short-chain acyl-CoA dehydrogenase deficiency.

A Historical Cohort Study on the Efficacy of Glucocorticoids and Riboflavin Among Patients with Late-onset Multiple Acyl-CoA Dehydrogenase Deficiency / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is the most common type of lipid storage myopathies in China. Most patients with late-onset MADD are well responsive to riboflavin. Up to now, these patients are often treated with glucocorticoids as the first-line drug because they are misdiagnosed as polymyositis without muscle biopsy or gene analysis. Although glucocorticoids seem to improve the fatty acid metabolism of late-onset MADD, the objective evaluation of their rationalization on this disorder and comparison with riboflavin treatment are unknown.</p><p><b>METHODS</b>We performed a historical cohort study on the efficacy of the two drugs among 45 patients with late-onset MADD, who were divided into glucocorticoids group and riboflavin group. Detailed clinical information of baseline and 1-month follow-up were collected.</p><p><b>RESULTS</b>After 1-month treatment, a dramatic improvement of muscle strength was found in riboflavin group (P < 0.05). There was no significant difference in muscle enzymes between the two groups. Significantly, the number of patients with full recovery in glucocorticoids group was less than the number in riboflavin group (P < 0.05). On the other hand, almost half of the patients in riboflavin group still presented high-level muscle enzymes and weak muscle strength after 1-month riboflavin treatment, meaning that 1-month treatment duration maybe insufficient and patients should keep on riboflavin supplement for a longer time.</p><p><b>CONCLUSIONS</b>Our results provide credible evidences that the overall efficacy of riboflavin is superior to glucocorticoids, and a longer duration of riboflavin treatment is necessary for patients with late-onset MADD.</p>

Skeletal Muscle Magnetic Resonance Imaging of the Lower Limbs in Late-onset Lipid Storage Myopathy with Electron Transfer Flavoprotein Dehydrogenase Gene Mutations / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lipid storage myopathy (LSM) is a genetically heterogeneous group with variable clinical phenotypes. Late-onset multiple acyl-coenzyme A dehydrogenation deficiency (MADD) is a rather common form of LSM in China. Diagnosis and clinical management of it remain challenging, especially without robust muscle biopsy result and genetic detection. As the noninvasion and convenience, muscle magnetic resonance imaging (MRI) is a helpful assistant, diagnostic tool for neuromuscular disorders. However, the disease-specific MRI patterns of muscle involved and its diagnostic value in late-onset MADD have not been systematic analyzed.</p><p><b>METHODS</b>We assessed the MRI pattern and fat infiltration degree of the lower limb muscles in 28 late-onset MADD patients, combined with detailed clinical features and gene spectrum. Fat infiltration degree of the thigh muscle was scored while that of gluteus was described as obvious or not. Associated muscular atrophy was defined as obvious muscle bulk reduction.</p><p><b>RESULTS</b>The mean scores were significantly different among the anterior, medial, and posterior thigh muscle groups. The mean of fat infiltration scores on posterior thigh muscle group was significantly higher than either anterior or medial thigh muscle group (P < 0.001). Moreover, the mean score on medial thigh muscle group was significantly higher than that of anterior thigh muscle group (P < 0.01). About half of the patients displayed fat infiltration and atrophy in gluteus muscles. Of 28 patients, 12 exhibited atrophy in medial and/or posterior thigh muscle groups, especially in posterior thigh muscle group. Muscle edema pattern was not found in all the patients.</p><p><b>CONCLUSIONS</b>Late-onset MADD patients show a typical muscular imaging pattern of fat infiltration and atrophy on anterior, posterior, and medial thigh muscle groups, with major involvement of posterior thigh muscle group and gluteus muscles and a sparing involvement of anterior thigh compartment. Our findings also suggest that muscle MRI of lower limbs is a helpful tool in guiding clinical evaluation on late-onset MADD.</p>

Clinical features and ACADVL gene mutation spectrum analysis of 11 Chinese patients with very long chain acyl-CoA dehydrogenase deficiency / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical and laboratory features of very long chain acyl-CoA dehydrogenase deficiency ( VLCADD ) and the correlations between its genotype and phenotype.</p><p><b>METHOD</b>Eleven patients diagnosed as VLCADD of Shanghai Jiaotong University School of Medicine seen from September 2006 to May 2014 were included. There were 9 boys and 2 girls, whose age was 2 d-17 years. Analysis was performed on clinical features, routine laboratory examination, and tandem mass spectrometry (MS-MS) , gas chromatography mass spectrometry (GC-MS) and genetic analysis were conducted.</p><p><b>RESULT</b>All cases had elevated levels of blood tetradecanoylcarnitine (C14:1) recognized as the characteristic biomarker for VLCADD. The eleven patients were classified into three groups: six cases in neonatal onset group, three in infancy onset group form patients and two in late onset group. Neonatal onset patients were characterized by hypoactivity, hypoglycemia shortly after birth. Infancy onset patients presented hepatomegaly and hypoglycemia in infancy. The two adolescent patients showed initial manifestations of exercise intolerance or rhabdomyolysis. Six of the eleven patients died at the age of 2-8 months, including four neonatal onset and two infant onset patients, with one or two null mutations. The other two neonatal onset patients were diagnosed since early birth through neonatal screening and their clinical manifestation are almost normal after treatments. Among 11 patients, seventeen different mutations in the ACADVL gene were identified, with a total mutation detection rate of 95.45% (21/22 alleles), including eleven reported mutations ( p. S22X, p. G43D, p. R511Q, p. W427X, p. A213T, p. C215R, p. G222R, p. R450H, p. R456H, c. 296-297delCA, c. 1605 + 1G > T) and six novel mutations (p. S72F, p. Q100X, p. M437T, p. D466Y, c. 1315delG insAC, IVS7 + 4 A > G). The p. R450H was the most frequent mutation identified in three alleles (13.63%, 3/22 alleles), followed by p. S22X and p. D466Y mutations which were detected in two alleles (9.09%, 2/22 alleles).</p><p><b>CONCLUSION</b>The ACADVL gene mutations were heterozygous in our patients. The mortality of neonatal onset form and infant onset form is much higher than the late onset form patients, suggesting a certain correlation between the genotype and phenotype was found. The earlier diagnosis and treatment of VLCADD are of vital importance for the improvement of the prognosis of the patients.</p>

Mutation analysis of a family with 2-Methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency / 中华儿科杂志

<p><b>OBJECTIVE</b>The aim of this study was to explore the genetic features of a family with 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency (MHBDD) which may provide the basis for the diagnosis and genetic counseling.</p><p><b>METHOD</b>Clinical data of the proband was collected, total RNA and genomic DNA were extracted from the peripheral blood. The whole coding region of the ACAT1 gene was amplified by RT-PCR. 5' noncoding region of the ACAT1 gene and all 6 exons and flanking intron regions of the HADH2 gene were amplified by PCR. All amplification products were directly sequenced and compared with the reference sequence.</p><p><b>RESULT</b>(1) The patient was a one-year-old boy who presented with psychomotor retardation and astasia when he was admitted to the hospital. Biochemical test revealed slight hyperlactatemia (3.19 mmol/L) and magnetic resonance imaging showed delayed myelination. 2-Methylacetoacetyl-CoA thiolase deficiency was suggested by gas chromatography-mass spectrometry. (2) There was no mutation in the ACAT1 gene and a hemizygous missense mutation c.388C > T was found in the 4 exon of the HADH2 gene which resulted in p. R130C. Proband's mother was the heterozygote and the father was normal.</p><p><b>CONCLUSION</b>This is the first report on MHBDD patient and HADH2 mutation in China. p.R130C is responsible for the pathogenesis of the disease in the infant.</p>

A Korean Family with Cholesterol Ester Transfer Protein Deficiency

A 32-year-old female patient and her sister show high levels of high density lipoprotein (HDL) cholesterol in regular health checkups, since female patient was 11 years old. The patient's serum total cholesterol was 285 mg/dL and HDL cholesterol was 113 mg/dL. Her sister's total cholesterol was 240 mg/dL and the HDL cholesterol measured to be 90 mg/dL. Lipoprotein pattern and cholesteryl ester transfer activity gene analysis were examined in these patients. We found c.1321+1G>A (IVS14+1G/A) hetero mutation in cholesteryl ester transfer protein (CETP) genes. Generally, CETP mediates transfer and exchange of triglycerides and cholesteryl ester between plasma lipoproteins. Also we investigated a key role of HDL-CE and Apo A-1 metabolism. Patients with low levels of CETP have increased serum HDL levels. We hereby report two Korean cases of CETP deficiency in a family. Brief literature review ensues with the cases.

MCT oil-based diet reverses hypertrophic cardiomyopathy in a patient with very long chain acyl-coA dehydrogenase deficiency.

Very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is one of the genetic defects of mitochondrial fatty acid beta-oxidation presenting in early infancy or childhood. If undiagnosed and untreated, VLCAD deficiency may be fatal, secondary to cardiac involvement. We assessed the effect of replacing part of the fat in the diet of a 2 ½-month-old male infant, who was diagnosed with VLCAD deficiency,with medium-chain triglyceride (MCT) oil and essential fats. The patient presented with vomiting, dehydration, and was found to have persistent elevation of liver function tests, hepatomegaly, pericardial and pleural effusion, right bundle branch block, and biventricular hypertrophy. Because of the cardiomyopathy, hepatomegaly, and an abnormal acylcarnitine profile and urine organic acids, he was suspected of having VLCAD deficiency. This was confirmed on acyl-coA dehydrogenase, very long chain (ACADVL) gene analysis. He was begun on an MCT oil-based formula with added essential fatty acids, uncooked cornstarch (around 1 year of age), and frequent feeds. By 7 months of age, cardiomyopathy had reversed and by 18 months of age, all cardiac medications were discontinued and hypotonia had improved such that physical therapy was no longer required. At 5 years of age, he is at the 50th percentile for height and weight along with normal development. Pediatricians need to be aware about the basic pathophysiology of the disease and the rationale behind its treatment as more patients are being diagnosed because of expansion of newborn screen. The use of MCT oil as a medical intervention for treatment of VLCAD deficiency remains controversial mostly because of lack of clear phenotype-genotype correlations, secondary to the genetic heterogeneity of the mutations. Our case demonstrated the medical necessity of MCT oil-based nutritional intervention and the need for the further research for the development of specific guidelines to improve the care of these patients.

Clinical and gene study of three pedigrees of phytosterolemia associated with macrothrombocytopenia and hemolysis / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the clinical features and ABCG5/ABCG8 gene mutations of three pedigrees of phytosterolemia presented with macrothrombocytopenia and hemolysis.</p><p><b>METHODS</b>Erythrocyte and platelet morphology were examined under light microscope. Plasma sterol levels were measured by high pressure/performance liquid chromatography method. All of ABCG5 and ABCG8 exons and intron-exon boundaries were directly sequenced to identify mutations, the corresponding gene mutation sites of three families members and healthy individuals were detected.</p><p><b>RESULTS</b>All the patients presented macrothrombocytopenia, hemolysis, splenomegaly and xanthomas. The blood smears showed large platelets, some as large as erythrocytes, and abnormal erythrocyte shapes, such as stomatocytes. Plasma concentrations of phytosterols, especially sitosterol were markedly elevated (30 fold) in the affected patients. Four mutations were identified in these three pedigrees, ABCG5 C20896T (R446X) and A20883G, ABCG8 del43683-43724 and del1938C-1939G/ins1938T. The latter three were novel mutations reported for the first time.</p><p><b>CONCLUSIONS</b>Phytosterolemia associated with macrothrombocytopenia and hemolysis is a new subtype of this disease. Plasma phytosterols and related gene analysis should be performed when ever an unexplained macrothrombocytopenia, especially combined with haemolysis or/and stomatocytosis.</p>

Clinical, Biochemical and Genetic Analyses in Two Korean Patients with Medium-chain Acyl-CoA Dehydrogenase Deficiency / 대한진단검사의학회지

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is an autosomal recessive hereditary metabolic disorder of mitochondrial fatty acid beta-oxidation. It is characterized by hypoketotic hypoglycemia, hyperammonemia, seizure, coma, and sudden infant death syndrome-like illness. The most frequently isolated mutation in the acyl-CoA dehydrogenase, medium-chain (ACADM) gene of Caucasian patients with MCADD is c.985A>G, but ethnic variations exist in the frequency of this mutation. Here, we describe 2 Korean pediatric cases of MCADD, which was detected during newborn screening by tandem mass spectrometry and confirmed by molecular analysis. The levels of medium-chain acylcarnitines, including octanoylcarnitine (C8), hexanoylcarnitine (C6), and decanoylcarnitine (C10), were typically elevated. Molecular studies revealed that Patient 1 was a compound heterozygote for c.449_452delCTGA (p.Thr150ArgfsX4) and c.461T>G (p.L154W) mutations, and Patient 2 was a compound heterozygote for c.449_452delCTGA (p.Thr150ArgfsX4) and c.1189T>A (p.Y397N) mutations. We detected asymptomatic patients with MCADD by using a newborn screening test and confirmed it by ACADM mutation analysis. This report presents evidence of the biochemical and molecular features of MCADD in Korean patients and, to the best of our knowledge, this is the first report of the c.461T>G mutation in the ACADM gene.