Sensory neuropathy as a manifestation of multiple acyl-coenzyme A dehydrogenase deficiency.

Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder which typically manifests with muscle weakness. However, despite late-onset MADD being treatable, it is often misdiagnosed, due in part to the heterogeneity of presentations. We report a case of late-onset MADD manifesting first as a sensory neuropathy before progressing to myopathic symptoms and acute metabolic decompensation. Early diagnostic workup with acylcarnitine profiling and organic acid analysis was critical in patient outcome; metabolic decompensation and myopathic symptoms were completely reversed with riboflavin supplementation and dietary modification, although sensory neuropathy persisted. Clinical consideration of MADD as part of the differential diagnosis of neuropathy with myopathy is crucial for a timely diagnosis and treatment of MADD.

The presence of white cell Jordan's anomaly in multiple Acyl-CoA dehydrogenase deficiency: A case report and implications for clinical practice.

BACKGROUND: Multiple Acyl-CoA Dehydrogenase Deficiency (MADD), also known as Glutaric Aciduria Type II, is an exceptionally rare autosomal recessive genetic disorder that disrupts the metabolism of fatty acids, amino acids, and choline. It presents with a wide range of clinical manifestations, from severe neonatal-onset forms to milder late-onset cases, with symptoms including metabolic disturbances and muscle weakness. Jordan's anomaly is a distinctive morphological feature found in peripheral blood white cells and is typically associated with Neutral Lipid Storage Disease (NLSD). CASE REPORT: In our case report, the patient initially presented with symptoms of vomiting, abdominal pain, and altered consciousness. The presence of white cell Jordan's anomaly was detected in the blood smear. Subsequent serum tests revealed elevated levels of transaminases, creatine kinase, uric acid, and multiple acylcarnitines, while blood glucose and free carnitine levels were notably reduced. High-throughput sequencing confirmed heterozygous pathogenic variants in the electron-transferring flavoprotein dehydrogenase (ETFDH) gene, leading to the conclusive diagnosis of MADD. Following a three-month treatment regimen involving high-dose vitamin B2, coenzyme Q10, and other supportive interventions, the patient exhibited significant clinical improvement, ultimately resulting in discharge. CONCLUSION: The identification of Jordan's anomaly in a pediatric patient with late-onset MADD sheds light on its broader implications within the realm of lipid storage myopathies. The significance of this finding extends beyond its conventional association with NLSD, challenging the notion of its exclusivity. This novel observation serves as a compelling reminder of the diagnostic significance this morphological abnormality holds, potentially revolutionizing diagnostic practices within the field.

The male-to-female ratio in late-onset multiple acyl-CoA dehydrogenase deficiency: a systematic review and meta-analysis.

BACKGROUND: Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is the most common lipid storage myopathy. There are sex differences in fat metabolism and it is not known whether late-onset MADD affects men and women equally. METHODS: In this systematic review and meta-analysis, the PubMed, Embase, Web of Science, CNKI, CBM, and Wanfang databases were searched until 01/08/2023. Studies reporting sex distribution in patients with late-onset MADD were included. Two authors independently screened studies for eligibility, extracted data, and assessed risk of bias. Pre-specified outcomes of interest were the male-to-female ratio (MFR) of patients with late-onset MADD, the differences of clinical characteristics between the sexes, and factors influencing the MFR. RESULTS: Of 3379 identified studies, 34 met inclusion criteria, yielding a total of 609 late-onset MADD patients. The overall pooled percentage of males was 58% (95% CI, 54-63%) with low heterogeneity across studies (I2 = 2.99%; P = 0.42). The mean onset ages, diagnostic delay, serum creatine kinase (CK), and allelic frequencies of 3 hotspot variants in ETFDH gene were similar between male and female patients (P > 0.05). Meta-regressions revealed that ethnic group was associated with the MFR in late-onset MADD, and subgroup meta-analyses demonstrated that East-Asian patients had a higher percentage of male, lower CK, and higher proportion of hotspot variants in ETFDH gene than non-East-Asian patients (P < 0.05). CONCLUSIONS: Male patients with late-onset MADD were more common than female patients. Ethnicity was proved to be a factor influencing the MFR in late-onset MADD. These findings suggest that male sex may be a risk factor for the disease.

A comparative study on riboflavin responsive multiple acyl-CoA dehydrogenation deficiency due to variants in FLAD1 and ETFDH gene.

Lipid storage myopathy (LSM) is a heterogeneous group of lipid metabolism disorders predominantly affecting skeletal muscle by triglyceride accumulation in muscle fibers. Riboflavin therapy has been shown to ameliorate symptoms in some LSM patients who are essentially concerned with multiple acyl-CoA dehydrogenation deficiency (MADD). It is proved that riboflavin responsive LSM caused by MADD is mainly due to ETFDH gene variant (ETFDH-RRMADD). We described here a case with riboflavin responsive LSM and MADD resulting from FLAD1 gene variants (c.1588 C > T p.Arg530Cys and c.1589 G > C p.Arg530Pro, FLAD1-RRMADD). And we compared our patient together with 9 FLAD1-RRMADD cases from literature to 106 ETFDH-RRMADD cases in our neuromuscular center on clinical history, laboratory investigations and pathological features. Furthermore, the transcriptomics study on FLAD1-RRMADD and ETFDH-RRMADD were carried out. On muscle pathology, both FLAD1-RRMADD and ETFDH-RRMADD were proved with lipid storage myopathy in which atypical ragged red fibers were more frequent in ETFDH-RRMADD, while fibers with faint COX staining were more common in FLAD1-RRMADD. Molecular study revealed that the expression of GDF15 gene in muscle and GDF15 protein in both serum and muscle was significantly increased in FLAD1-RRMADD and ETFDH-RRMADD groups. Our data revealed that FLAD1-RRMADD (p.Arg530) has similar clinical, biochemical, and fatty acid metabolism changes to ETFDH-RRMADD except for muscle pathological features.

Clinical, biochemical, and genetic spectrum of MADD in a South African cohort: an ICGNMD study.

BACKGROUND: Multiple acyl-CoA dehydrogenase deficiency (MADD) is an autosomal recessive disorder resulting from pathogenic variants in three distinct genes, with most of the variants occurring in the electron transfer flavoprotein-ubiquinone oxidoreductase gene (ETFDH). Recent evidence of potential founder variants for MADD in the South African (SA) population, initiated this extensive investigation. As part of the International Centre for Genomic Medicine in Neuromuscular Diseases study, we recruited a cohort of patients diagnosed with MADD from academic medical centres across SA over a three-year period. The aim was to extensively profile the clinical, biochemical, and genomic characteristics of MADD in this understudied population. METHODS: Clinical evaluations and whole exome sequencing were conducted on each patient. Metabolic profiling was performed before and after treatment, where possible. The recessive inheritance and phase of the variants were established via segregation analyses using Sanger sequencing. Lastly, the haplotype and allele frequencies were determined for the two main variants in the four largest SA populations. RESULTS: Twelve unrelated families (ten of White SA and two of mixed ethnicity) with clinically heterogeneous presentations in 14 affected individuals were observed, and five pathogenic ETFDH variants were identified. Based on disease severity and treatment response, three distinct groups emerged. The most severe and fatal presentations were associated with the homozygous c.[1067G > A];c.[1067G > A] and compound heterozygous c.[976G > C];c.[1067G > A] genotypes, causing MADD types I and I/II, respectively. These, along with three less severe compound heterozygous genotypes (c.[1067G > A];c.[1448C > T], c.[740G > T];c.[1448C > T], and c.[287dupA*];c.[1448C > T]), resulting in MADD types II/III, presented before the age of five years, depending on the time and maintenance of intervention. By contrast, the homozygous c.[1448C > T];c.[1448C > T] genotype, which causes MADD type III, presented later in life. Except for the type I, I/II and II cases, urinary metabolic markers for MADD improved/normalised following treatment with riboflavin and L-carnitine. Furthermore, genetic analyses of the most frequent variants (c.[1067G > A] and c.[1448C > T]) revealed a shared haplotype in the region of ETFDH, with SA population-specific allele frequencies of < 0.00067-0.00084%. CONCLUSIONS: This study reveals the first extensive genotype-phenotype profile of a MADD patient cohort from the diverse and understudied SA population. The pathogenic variants and associated variable phenotypes were characterised, which will enable early screening, genetic counselling, and patient-specific treatment of MADD in this population.

A case report on multiple acyl-CoA dehydrogenase deficiency with severe myopathy and osteoporosis.

A 35-year-old male patient presented fluctuating bilateral lower extremity weakness for 3 years. Physical examination showed grade 4 proximal muscle weakness in both lower extremities and grade 5 distal muscle weakness. Laboratory data revealed elevated creatine kinase, triglycerides, and cholesterol. Muscle pathology showed deposition of lipid droplet under the sarcolemma. Bone densitometry indicated severe osteoporosis. Next-generation sequencing revealed a pathogenic mutation in the ETFDH gene. The patient was diagnosed with late-onset multiple acyl-CoA dehydrogenase deficiency. After riboflavin treatment, symptoms of the patient were relieved, physical endurance was restored, and bone mineral density was improved.

Late-onset multiple acyl-CoA dehydrogenase deficiency: an insidious presentation.

Multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare inborn error of metabolism that results in impairment of mitochondrial ß-oxidation of fatty acids. It is inherited in an autosomal recessive manner and impairs electron transfer in the electron transport chain. The clinical manifestations of MADD are highly variable and include exercise intolerance, myopathy, cardiomyopathy, encephalopathy, coma and death. Early-onset MADD is often associated with a high mortality with significant number of patients presenting with severe metabolic acidosis, non-ketotic hypoglycaemia and/or hyperammonaemic presentations. While late-onset MADD is suggested to have a lower mortality, the severe encephalopathic presentations may well be under-reported as a diagnosis of MADD may not be considered.MADD is treatable with riboflavin and appropriate nutrition with a focus on prevention and early management of metabolic decompensation. The neonatal phenotype differs significantly from late-onset MADD, where diagnosis may be delayed due to heterogeneity in clinical features, atypical presentation and confounding comorbidities, together with lower awareness among physicians.This report describes a woman in her 30s who presented with acute-onset ataxia, confusion and hyperammonaemic encephalopathy requiring intubation. Subsequent biochemical investigation revealed a diagnosis of MADD. At present, there are no national guidelines in Australia for the management of MADD. This case highlights the investigation and treatment of late-onset MADD.

An unusual presentation of type III late onset multiple-acyl-CoA dehydrogenase deficiency leading to a review of its classification system.

Multiple-acyl-CoA dehydrogenase deficiency (MADD) is a rare autosomal recessive disorder which can be split into three types. Type III MADD is associated with acute or subacute proximal muscle weakness and other variable non-specific features making it a challenging diagnosis for the clinician. This case report describes MADD in a 64 year-old lady, thought to be one of the latest first presentations of the disease. Unusually for this condition, the initial presentation was with dyspnoea. Furthermore, since this case provides further evidence that gene variants can predict age of onset, we advocate for further subclassification of type III MADD into late onset MADD (LO-MADD) when homozygous gene variants are present and very LO-MADD when heterozygous gene variants are found.

Incorporating second-tier genetic screening for multiple acyl-CoA dehydrogenase deficiency.

BACKGROUND: Newborn screening (NBS) for multiple acyl-CoA dehydrogenase deficiency (MADD) has poor sensitivity. This study aimed to evaluate the feasibility of incorporating second-tier genetic screening for MADD. METHODS: A total of 453,390 newborns were screened for inherited metabolic disorders using tandem mass spectrometry from January 2017 to May 2022. A matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) assay was developed to identify 23 common ETFDH variants and used for second-tier screening of MADD. RESULTS: Overall, 185 newborns with suspected MADD received second-tier genetic screening. Thirty-three (17.8 %) newborns with positive results, of which 7 were homozygotes, 5 were compound heterozygotes, 21 were heterozygotes. Further genetic analysis revealed that 6 of the 21 newborns had a second ETFDH variant. Therefore, 18 patients were finally diagnosed with MADD, with a positive predictive value of 9.73 %. The detection rate and diagnostic rate of MALDI-TOF MS assay were 83.33 % and 66.67 %, respectively. Thus the incidence of MADD in our population was estimated at 1:25,188. Nine different ETFDH variants were identified in MADD patients. The most common ETFDH variant being c.250G > A with an allelic frequency of 47.22 %, followed by c.524G > A (13.89 %) and c.998A > G (13.89 %). All patients had elevation of multiple acylcarnitines at NBS. However, seven patients had normal acylcarnitine levels and two patients showed mild elevation of only two acylcarnitines during the recall review. CONCLUSION: We have established a high throughput MALDI-TOF MS assay for MADD screening. Half of the MADD patients would not be detected under conventional screening protocols. Incorporating second-tier genetic screening into the current NBS could improve the performance of MADD NBS.

Triagem neonatal por espectrometria de massas em tandem (MS/MS) para detecção da deficiência de acil-CoA desidrogenase de cadeia média (MCADD) / Neonatal screening by tandem mass spectrometry (MS/MS) for detection of medium-chain acyl-CoA dehydrogenase deficiency (MCADD)

INTRODUÇÃO: A MCADD é o distúrbio mais frequente da beta-oxidação mitocondrial dos ácidos graxos. No Brasil, a comparação de estudos epidemiológicos nacionais com dados da experiência do Distrito Federal com a triagem neonatal por MS/MS para MCADD sugerem um subdiagnóstico dessa condição no Brasil. A MCADD é uma doença grave, cujas manifestações clínicas geralmente iniciam no primeiro ano de vida. Os sintomas mais comuns incluem hipoglicemia hipocetótica recorrente, letargia, vômitos, disfunção hepática aguda, episódios semelhantes à síndrome de Reye, convulsões, coma e morte súbita. O seu diagnóstico precoce, possibilitado pela triagem neonatal por MS/MS, representa uma estratégia importante para a realização do tratamento oportuno e prevenção de óbitos e sequelas. TECNOLOGIA: Triagem neonatal por espectrometria de massas em tandem (MS/MS) em sangue seco, colhido em papelfiltro. PERGUNTA DE PESQUISA: A triagem neonatal (em sangue seco, colhido em papel-filtro) por MS/MS, para a detecção da MCADD, em recém-nascidos assintomáticos, é custo-efetiva e reduz a mortalidade e as complicações de curto e longo prazo naqueles recém-nascidos nos quais a doença é detectada, em comparação ao diagnóstico dessa doença em indivíduos com suspeita clínica ou manifestações clínicas? EVIDÊNCIAS CLINICAS: Em uma revisão sistemática da literatura, realizada em 26 de abril de 2022, foram encontradas 1037 referências, das quais 7 atendiam aos critérios de inclusão deste relatório (6 avaliaram desfechos primários e 1 avaliou desfechos secundários). Considerando os 4 desfechos primários avaliados, não foram encontrados estudos sobre apenas um deles (qualidade de vida). Os estudos incluídos descrevem maior frequência de morte súbita ou por complicações da doença, e de internações hospitalares decorrentes da doença ou de suas complicações no grupo comparador (indivíduos com suspeita clínica ou com manifestações clínicas de MCADD). Com relação à incidência de complicações ou condições resultantes da doença, independente da necessidade de admissão hospitalar, também há uniformidade entre os resultados dos estudos incluídos, indicando a eficácia/eficiência da intervenção. AVALIAÇÃO ECONÔMICA (AE) propôs-se uma análise de custo-utilidade construída com base nas diretrizes metodológicas publicadas pelo Ministério da Saúde, na perspectiva do SUS, tendo como população alvo todos os recém-nascidos no país. De acordo com a análise empreendida, o custo da triagem por MS/MS para MCADD foi de R$ 1.952,88, havendo um incremento em custos de cerca de R$ 1.949,00 em comparação à não-realização da triagem neonatal para esta doença. No entanto, a efetividade comparada da triagem por MS/MS foi superior à estratégia de não triar esta doença, mais do que o dobro daquela associada à não-triagem, havendo um incremento de cerca de 78 pontos nesta. Por fim, a Razão de Custo-efetividade Incremental (RCEI) encontrada foi de R$ 24,99/QALY. ANÁLISE DE IMPACTO ORÇAMENTÁRIO (AIO): foi feita uma avaliação do impacto orçamentário da possível incorporação do referido teste (MS/MS) ao longo de 5 anos, junto com a substituição da testagem para fenilcetonúria (PKU) pelo método de imunofluorimetria (o atualmente usado) pela mesma metodologia (MS/MS), conforme as Diretrizes Metodológicas de análise de Impacto Orçamentário do Ministério da Saúde. A realidade atual de inexistência de testagem de MCADD gera um custo anual em teste de triagem de zero. No entanto, a não identificação de indivíduos com MCADD, gera, por sua vez, custos de internação. Sendo assim, no primeiro caso o custo anual e em 5 anos seria zero. Porém se fossem considerados os custos gerados a partir dos pacientes sem diagnóstico neonatal que evoluíram a sintomas e internação no primeiro ano de vida, a estimativa em cinco anos seria de um gasto de pouco mais de R$ 100 mil. A triagem para MCADD por MS/MS descontados apenas os custos das internações evitadas com a identificação precoce daqueles com esta doença pela triagem, ficaria em cerca de R$ 288 milhões ao longo de 5 anos, sendo a média anual aproximadamente R$ 57 milhões. No entanto, considerando que a triagem por fenilcetonúria (PKU), hoje realizada por imunofluorimetria, com a adoção da triagem por MS/MS, poderia ser feita por esta última metodologia, sem que com isso houvesse acréscimo no gasto do exame realizado para MCADD (ou seja, o mesmo teste, triaria ao mesmo tempo MCADD e PKU) haveria uma economia adicional advinda dos custos salvos pela não realização da imunofluorimetria para PKU. Assim, ao considerar-se a triagem neonatal por MS/MS para MCADD e PKU ao longo de 5 anos, com todos os custos evitados (possíveis internações por sintomas da doença no primeiro ano de vida e utilização da imunofluorimetria como método da triagem para a fenilcetonúria), este valor seria cerca de R$ 222 milhões, resultando num dispêndio anual médio de cerca de R$ 44 milhões, ou seja, uma economia média anual adicional de 13 milhões apenas com a inclusão da triagem de PKU na mesma metodologia utilizada para triagem de MCADD. CONSIDERAÇÕES FINAIS: os resultados sugerem que os indivíduos com MCADD são beneficiados com a inclusão da triagem neonatal para a detecção dessa doença. A avaliação econômica mostra que a efetividade da triagem neonatal por MS/MS é de cerca de 153, sendo este valor mais que o dobro da efetividade associada à não-triagem (cerca de 75); a efetividade incremental é de 78. Já a RCEI encontrada foi de R$ 24,99/QALY. Esta análise indica ganhos evidentes da estratégia de adoção de triagem neonatal por MS/MS para MCADD. Em relação ao impacto econômico, ao longo de 5 anos, com todos os custos evitados (referentes às possíveis internações por sintomas da doença nos primeiros anos de vida e testagem conjunta de MCADD e PKU por MS/MS), este valor seria cerca de R$ 222 milhões, um dispêndio anual médio de cerca de R$ 44 milhões, uma economia média anual adicional de 13 milhões apenas com a inclusão da triagem de PKU na mesma metodologia utilizada para triagem de MCADD. RECOMENDAÇÃO PRELIMINAR DA CONITEC: na 113ª Reunião Ordinária da Conitec, realizada em 05 de outubro de 2022, os membros presentes no Plenário deliberaram por unanimidade que a matéria fosse disponibilizada em consulta pública com recomendação preliminar favorável à incorporação da triagem neonatal por espectrometria de massas em tandem (MS/MS), para a detecção da deficiência de MCADD. Para essa recomendação, a Conitec considerou que a detecção precoce por triagem neonatal da MCADD é eficaz, segura e custo-efetiva, estando de acordo com os critérios estabelecidos na Lei Nº 14.154, de 26 de maio de 2021, que dispõe sobre a ampliação do Programa Nacional de Triagem Neonatal (PNTN). CONSULTA PÚBLICA: : a consulta pública n° 70 ficou vigente no período entre 25/10/2022 e 14/11/2022. Foram recebidas 10 contribuições, sendo 4 da categoria técnico-científicas e 6 de experiência ou opinião. Todos os participantes estiveram de acordo com a recomendação preliminar da Conitec de incorporar a triagem neonatal por espectrometria de massas em tandem (MS/MS) para detecção da deficiência de acil-CoA desidrogenase de cadeia média (MCADD) no SUS. A consulta pública não adicionou elementos que alterassem o conteúdo deste relatório de recomendação. RECOMENDAÇÃO FINAL DA CONITEC: os membros do Plenário da Conitec, presentes em sua 12ª Reunião Extraordinária, realizada no dia 29 de novembro de 2022, deliberaram por unanimidade, recomendar a incorporação da triagem neonatal por espectrometria de massas em tandem (MS/MS) para detecção da deficiência de acilCoA desidrogenase de cadeia média (MCADD). Foi assinado o Registro de Deliberação nº 789/2022. DECISÃO: Incorporar, no âmbito do Sistema Único de Saúde - SUS, a triagem neonatal por espectrometria de massas em tandem (MS/MS) para detecção da deficiência de acilCoA desidrogenase de cadeia média (MCADD), conforme protocolo estabelecido pelo Ministério da Saúde, conforme a Portaria nº 179, publicada no Diário Oficial da União nº 244, seção 1, página 304, em 28 de dezembro de 2022.

A fatal case of neonatal onset multiple acyl-CoA dehydrogenase deficiency caused by novel mutation of ETFDH gene: case report.

BACKGROUND: Multiple acyl-CoA dehydrogenase deficiency (MADD) or glutaric aciduria type II is an extremely rare autosomal recessive inborn error of fatty acid beta oxidation and branched-chain amino acids, secondary to mutations in the genes encoding the electron transfer flavoproteins A and B (ETFs; ETFA or ETFB) or ETF dehydrogenase (ETFDH). The clinical manifestation of MADD are heterogeneous, from severe neonatal forms to mild late-onset forms. CASE PRESENTATION: We report the case of a preterm newborn who died a few days after birth for a severe picture of untreatable metabolic acidosis. The diagnosis of neonatal onset MADD was suggested on the basis of clinical features displaying congenital abnormalities and confirmed by the results of expanded newborn screening, which arrived the day the newborn died. Molecular genetic test revealed a homozygous indel variant c.606 + 1 _606 + 2insT in the ETFDH gene, localized in a canonical splite site. This variant, segregated from the two heterozygous parents, is not present in the general population frequency database and has never been reported in the literature. DISCUSSION AND CONCLUSION: Recently introduced Expanded Newborn Screening is very important for a timely diagnosis of Inherited Metabolic Disorders like MADD. In some cases which are the most severe, diagnosis may arrive after symptoms are already present or may be the neonate already died. This stress the importance of collecting all possible samples to give parents a proper diagnosis and a genetic counselling for future pregnacies.

Characterization of 31 Patients with Riboflavin-Responsive Multiple acyl-CoA Dehydrogenase Deficiency

Aims: To evaluate the clinical, pathological, and genetic features of patients with riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency (RR-MADD). Methods: Thirty-one patients with RR-MADD admitted to our hospital from January 2005 to November 2020 were enrolled, and their clinical data were collected. Pathological characteristics of the muscle tissue and possible pathogenic gene mutations were analyzed. Results: The most common clinical features in all patients were symmetrical proximal muscle weakness. Laboratory examination revealed elevated levels of creatine kinase, homocysteine, and uric acid, acylcarnitines, and organic acid. The muscle biopsy revealed typical pathological changes like lipid deposition. Genetic analysis identified ETFDH mutations in 29 patients, among which one had homozygotes, 19 had compound heterozygotes, 7 had heterozygous mutations, and 2 had heterozygous mutations of both ETFDH and ETFA. Two patients had no pathogenic gene mutations. All patients were treated with riboflavin, and their symptoms improved, which was consistent with the diagnosis of RR-MADD. Conclusion: The clinical manifestations and genetic test results of patients with RR-MADD are heterogeneous. Therefore, a comprehensive analysis of clinical, pathological, and genetic testing is essential for the early diagnosis of RR-MADD.

Features and diagnostic value of body composition in patients with late-onset multiple acyl-CoA dehydrogenase deficiency.

OBJECTIVE: This study aims to analyse the body composition features and its changes after treatment in patients with late-onset multiple acyl-CoA dehydrogenase deficiency (MADD). METHODS: Body composition was measured in patients with late-onset MADD, inflammatory myopathies, mitochondrial myopathy, and healthy controls. The correlation analyses between body composition and traditional parameters were performed. Comparisons between groups and receiver operating characteristic curve analyses were performed. RESULTS: A total of 42 participants included 13 patients with late-onset MADD, 13 healthy controls, 10 with inflammatory myopathy, and 6 with mitochondrial myopathy. Bilateral grip strength and forced vital capacity (FVC) were moderate-strong correlated with skeletal muscle mass (right hand grip strength: r = 0.728, P < 0.001; left hand grip strength: r = 0.676, P < 0.001; FVC: r = 0.754, P < 0.001). Serum CK was moderately and negatively correlated with right hand grip strength (r = - 0.618, P = 0.005), left hand grip strength (r = - 0.630, P = 0.004), FVC (r = - 0.665, P = 0.002), manual muscle testing (MMT) (r = - 0.729, P = 0.000), and lean body mass skeletal muscle percentage (r = - 0.501, P = 0.029). Body composition features in patients with late-onset MADD were as follows: (1) obvious fat accumulation, (2) reduction of muscle mass, and (3) reduction of body water and intracellular water ratio. Some indicators of body composition were found to be valuable in diagnosis and eliminating differential diagnoses, such as visceral fat area (sensitivity 84.62%; specificity 92.31%; AUC 0.905) and fat mass (sensitivity 84.62%; specificity 75.00%; AUC 0.837). Seven patients were followed-up (2-9 months). Prior to treatment, the changes in body composition in these patients were conflicting. CONCLUSIONS: Hand grip strength and FVC were strongly associated with body composition. Body composition features in late-onset MADD are fat accumulation, muscle loss, decrease in total body water, and intracellular water ratio. Body composition features are valuable for diagnosis and assessment.

Clinical, pathological and genetic features and follow-up of 110 patients with late-onset MADD: a single-center retrospective study.

To observe a long-term prognosis in late-onset multiple acyl-coenzyme-A dehydrogenation deficiency (MADD) patients and to determine whether riboflavin should be administrated in the long-term and high-dosage manner, we studied the clinical, pathological and genetic features of 110 patients with late-onset MADD in a single neuromuscular center. The plasma riboflavin levels and a long-term follow-up study were performed. We showed that fluctuating proximal muscle weakness, exercise intolerance and dramatic responsiveness to riboflavin treatment were essential clinical features for all 110 MADD patients. Among them, we identified 106 cases with ETFDH variants, 1 case with FLAD1 variants and 3 cases without causal variants. On muscle pathology, fibers with cracks, atypical ragged red fibers (aRRFs) and diffuse decrease of SDH activity were the distinctive features of these MADD patients. The plasma riboflavin levels before treatment were significantly decreased in these patients as compared to healthy controls. Among 48 MADD patients with a follow-up of 6.1 years on average, 31 patients were free of muscle weakness recurrence, while 17 patients had episodes of slight muscle weakness upon riboflavin withdrawal, but recovered after retaking a small-dose of riboflavin for a short-term. Multivariate Cox regression analysis showed vegetarian diet and masseter weakness were independent risk factors for muscle weakness recurrence. In conclusion, fibers with cracks, aRRFs and diffuse decreased SDH activity could distinguish MADD from other genotypes of lipid storage myopathy. For late-onset MADD, increased fatty acid oxidation and reduced riboflavin levels can induce episodes of muscle symptoms, which can be treated by short-term and small-dose of riboflavin therapy.

Screening of multiple acyl-CoA dehydrogenase deficiency in newborns and follow-up of patients.

To investigate the incidence rate, clinical and gene mutation characteristics of multiple acyl-CoA dehydrogenase deficiency (MADD) in newborns in Zhejiang province. A total of 3 896 789 newborns were screened for MADD using tandem mass spectrometry in Zhejiang Neonatal Screening Center during January 2009 and December 2020. Patients of MADD were confirmed by urine organic acid and electron transferring flavoprotein (or electron transferring flavoprotein dehydrogenase () gene detection. MADD patients were given diet and life management, supplemented with L-carnitine, riboflavin and coenzyme Q 10 treatment, and their growth and intellectual development were evaluated during the followed up.Thirteen patients with MADD were diagnosed, with an incidence of 1/299 753. One patient was type Ⅱ, and the rest were type Ⅲ. Patients were followed up for 1 case died, 4 cases had acute metabolic disorders with hypoglycemia as the main manifestation due to infection, 1 case had hypotonia, and the rest 7 cases developed well. Patients had raised levels of C4-C18:1 acylcarnitines in the initial screening. Thirteen children were genetically tested, 1 case with compound heterozygous mutation in the gene, 1 case with homozygous mutation in the gene, 1 case with compound heterozygous mutation in the gene, 8 cases with compound heterozygous mutation and 1 case with homozygous mutation in the gene, 1 case that only 1 locus of gene was detected. The c.250G>A was the hotspot mutation in this study.The clinical manifestations of MADD are highly heterogeneous. The neonatal-onset form is serious, and late onset form usually has no obvious clinical symptoms. C4-C18:1 acylcarnitines usually increased in the initial screening, and the hotspot gene mutation is c.250G>A.

[Consensus on screening, diagnosis and treatment of multiple acyl-CoA dehydrogenase deficiency].

Multiple acyl-CoA dehydrogenase deficiency (MADD), also known as glutaricacidemia type II, is a relatively common disorder of fatty acid oxidation metabolism. The clinical manifestations are highly heterogeneous, symptoms can develop from newborn to adulthood. Neonatal onset type is more serious with high mortality. The symptoms of late onset patients include lipid deposition myopathy and vomiting, liver disease, and encephalopathy. Analysis of blood acyl carnitine spectrum by tandem mass spectrometry can be used for the screening. Late onset patients have relatively good prognosis with vitamin B2 treatment. The purpose of this consensus is to standardize the diagnosis, treatment and management of MADD, so as to improve the prognosis of patients and reduce death and disability.

Newborn screening and molecular features of patients with multiple acyl-CoA dehydrogenase deficiency in Quanzhou, China.

OBJECTIVES: Multiple acyl-CoA dehydrogenase deficiency (MADD) is an autosomal recessive disorder of fatty acid, amino acid and choline metabolism. Late-onset MADD is caused by ETFDH mutations and is the most common lipid storage myopathy in China. However, few patients with MADD have been identified through newborn screening (NBS). This study assessed the acylcarnitine profiles and molecular features of patients with MADD identified through NBS. METHODS: From January 2014 to June 2020, 479,786 newborns screened via tandem mass spectrometry were recruited for this study. Newborns with elevated levels of multiple acylcarnitines were recalled, those who tested positive in the reassessment were referred for genetic analysis. RESULTS: Of 479,786 newborns screened, six were diagnosed with MADD. The MADD incidence in the Chinese population was estimated to be 1:79,964. Initial NBS revealed five patients with typical elevations in the levels of multiple acylcarnitines; however, in one patient, acylcarnitine levels were in the normal reference range during recall. Notably, one patient only exhibited a mildly increased isovalerylcarnitine (C5) level at NBS. The patient with an atypical acylcarnitine profile was diagnosed with MADD by targeted gene sequencing. Six distinct ETFDH missense variants were identified, with the most common variant being c.250G>A (p.A84T), with an allelic frequency of 58.35 (7/12). CONCLUSIONS: These findings revealed that it is easy for patients with MADD to go unidentified, as they may have atypical acylcarnitine profiles at NBS and the recall stage, indicating the value of genetic analysis for confirming suspected inherited metabolic disorders in the NBS program. Therefore, false-negative (FN) results may be reduced by combining tandem mass spectrometry (MS/MS) with genetic testing in NBS for MADD.

A systematic review of late-onset and very-late-onset multiple acyl-coenzyme A dehydrogenase deficiency: Cohort analysis and patient report from Taiwan.

Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder with a dramatic clinical presentation. It was recently discovered that MADD may present at an advanced age. The clinical and laboratory data of an index patient and patients previously diagnosed at our institution were collected. A systematic review of previous studies retrieved from the PubMed, MEDLINE, and Embase databases published by February 1, 2020 was performed to collect patients with very-late-onset MADD (VLO-MADD, onset age > 60 years) globally and patients with late-onset MADD (LO-MADD, onset age < 60 years) in Taiwan. The clinical characteristics of the VLO-MADD patients were compared to those of LO-MADD patients. We report a patient with VLO-MADD who developed the first symptom at the age of 61 years. The patient presented with a Reye-like syndrome after taking aspirin for coronary artery disease. Repeated bouts of weakness were noted. Two variants of c.250 G > A (;) 419C > T were observed in the ETFDH gene. Another four patients with VLO-MADD were identified globally. Eighteen patients with LO-MADD were collected from our department and previously reported patients in Taiwan. There was no difference in the clinical symptoms (except for the onset age) or laboratory data between these two groups. Homozygous variants were not observed in any patients in the VLO-MADD group but were detected in 12 patients (66.6%) in the LO-MADD group (p = 0.014). Patients with MADD may first show symptoms in their 6th decade or beyond. The disease course may lead to erroneous diagnoses in this age group.

Prenatal diagnosis of glutaric acidemia type 2 with the use of exome sequencing - an up-to-date review and new case report.

INTRODUCTION: Inborn errors of metabolism (IEM) also called metabolic diseases constitute a large and heterogenous group of disorders characterized by a failure of essential cellular functions. Antenatal manifestation of IEM is absent or nonspecific, which makes prenatal diagnosis challenging. Glutaric acidemia type 2 (GA2) is a rare metabolic disease clinically manifested in three different ways: neonatal-onset with congenital anomalies, neonatal-onset without congenital anomalies and late-onset. Neonatal forms are usually lethal. Congenital anomalies present on prenatal ultrasound as large, hyperechoic or cystic kidneys with reduced amniotic fluid volume. MATERIAL AND METHODS: We present a systematic literature review describing prenatal diagnosis of GA2 and a new prenatal case. RESULTS: Ten prenatally diagnosed cases of GA2 have been published to date, mainly based on biochemical methods. New case of GA2 was diagnosed using exome sequencing method. DISCUSSION: All prenatal cases from literature review had positive history of GA2 running in the family. In our study trio exome sequencing was performed in case of fetal hyperechoic kidneys without a history of GA2. Consequently, we were able to identify two novel pathogenic variants of the ETFDH gene and to indicate their parental origin. SUMMARY: Exome sequencing approach used in case of fetal hyperechoic kidneys allows to identify pathogenic variants without earlier knowledge of the precise genetic background of the disease. Hyperechoic, enlarged kidneys could be one of the clinical features of metabolic diseases. After exclusion of chromosomal abnormalities, urinary tract obstruction and intrauterine infections, glutaric acidemia type 2 and number of monogenic disorders should be consider.