Vaccination strategies for people living with inborn errors of metabolism in Brazil

Abstract Objective: Through a literature review, make recommendations regarding immunizations in people living with Inborn Error of Metabolism (IEM) in Brazil, assess the possible impact on metabolic decompensations after immunization, and if this specific population may have an impaired immune response to vaccines. Source of data: The MeSH Terms vaccination OR vaccine OR immunization associated with the term inborn error of metabolism AND recommendation were used in combination with search databases. Only articles published after 1990, in the languages English, Spanish, French or Portuguese, human-related were included. Synthesis of data: A total of 44 articles were included to make the following recommendations. Individuals with IEMs need to be up to date with their immunizations. Regarding which vaccines should be offered, children and adults should follow the routine immunization schedules locally available, including the COVID-19 vaccines. The only exception is the rotavirus vaccine for hereditary fructose intolerance. The benefit of immunization outweighs the very low risk of metabolic decompensation. Since not all patients will have an adequate immune response, measuring antibody conversion and titers is recommended Conclusions: All patients should receive age-appropriate immunizations in their respective schedules without delays. The only situation when vaccination may be contraindicated is with oral rotavirus vaccine in hereditary fructose intolerance. Monitoring the levels of antibodies should be done to detect any immune dysfunction or the necessity for boosters. A personalized immunization schedule is ideal for patients with IEMs. The reference organizations could improve their recommendations to address all IEMs, not only some of them.

Research progress on renal calculus associate with inborn error of metabolism / 浙江大学学报·医学版

Renal calculus is a common disease with complex etiology and high recurrence rate. Recent studies have revealed that gene mutations may lead to metabolic defects which are associated with the formation of renal calculus, and single gene mutation is involved in relative high proportion of renal calculus. Gene mutations cause changes in enzyme function, metabolic pathway, ion transport, and receptor sensitivity, causing defects in oxalic acid metabolism, cystine metabolism, calcium ion metabolism, or purine metabolism, which may lead to the formation of renal calculus. The hereditary conditions associated with renal calculus include primary hyperoxaluria, cystinuria, Dent disease, familial hypomagnesemia with hypercalciuria and nephrocalcinosis, Bartter syndrome, primary distal renal tubular acidosis, infant hypercalcemia, hereditary hypophosphatemic rickets with hypercalciuria, adenine phosphoribosyltransferase deficiency, hypoxanthine-guanine phosphoribosyltransferase deficiency, and hereditary xanthinuria. This article reviews the research progress on renal calculus associated with inborn error of metabolism, to provide reference for early screening, diagnosis, treatment, prevention and recurrence of renal calculus.

Treatment and management for children with urea cycle disorder in chronic stage / 浙江大学学报·医学版

Urea cycle disorder (UCD) is a group of inherited metabolic diseases with high disability or fatality rate, which need long-term drug treatment and diet management. Except those with Citrin deficiency or liver transplantation, all pediatric patients require lifelong low protein diet with safe levels of protein intake and adequate energy and lipids supply for their corresponding age; supplementing essential amino acids and protein-free milk are also needed if necessary. The drugs for long-term use include nitrogen scavengers (sodium benzoate, sodium phenylbutyrate, glycerol phenylbutyrate), urea cycle activation/substrate supplementation agents (N-carbamylglutamate, arginine, citrulline), etc. Liver transplantation is recommended for pediatric patients not responding to standard diet and drug treatment, and those with severe progressive liver disease and/or recurrent metabolic decompensations. Gene therapy, stem cell therapy, enzyme therapy and other novel technologies may offer options for treatment in UCD patients. The regular biochemical assessments like blood ammonia, liver function and plasma amino acid profile are needed, and physical growth, intellectual development, nutritional intake should be also evaluated for adjusting treatment in time.

Córnea plana congénita y error innato del metabolismo en un niño

Introducción: La córnea plana congénita es una rara anomalía de herencia autosómica dominante o recesiva. Los defectos del ciclo de la urea son errores innatos del metabolismo que puede producir encefalopatía progresiva. Objetivo: Describir las características clínicas de un paciente con diagnósticos de córnea plana congénita y error innato del metabolismo. Presentación del caso: Paciente masculino de 7 años de edad, miembro de la cuarta generación de una familia con diagnóstico de córnea plana congénita. Al examen oftalmológico se observó en ambos ojos esclerización superior del limbo, aplanamiento corneal generalizado y cámaras anteriores estrechas. La topografía corneal mostró patrones esféricos y aplanamiento corneal más prominente en la media y extrema periferia. A la edad de 5 años comenzó a presentar ataxia recurrente, crisis epilépticas de inicio focal motoras clónicas en el hemicuerpo derecho y vómitos. Ingresó en estado de coma en la unidad de cuidados intensivos pediátricos del Hospital Pediátrico Universitario "William Soler". Se planteó encefalopatía progresiva por trastorno en el ciclo de la urea luego de constatarse hiperamonemia (error congénito del metabolismo), sin acidosis metabólica. Conclusiones: La córnea plana congénita es una enfermedad caracterizada por aplanamiento corneal generalizado con repercusión en la calidad visual. Los errores innatos del metabolismo debidos a trastornos en el ciclo de la urea se caracterizan por manifestaciones neurológicas graves con peligro potencial para la vida. Resulta novedosa la presentación de estas dos enfermedades infrecuentes en un mismo paciente, asociación que no aparece publicada con anterioridad.

Introduction: Congenital flat cornea is a rare anomaly of dominant or recessive autosomal inheritance. Urea cycle defects are inborn errors of metabolism that can lead to progressive encephalopathy. Objective: To describe the clinical characteristics of a patient with diagnoses of congenital flat cornea and inborn error of metabolism. Case Presentation: A 7-year-old male patient, member of the fourth generation of a family diagnosed with congenital flat cornea. Ophthalmological examination showed upper limbal sclerization, generalized corneal flattening and narrow anterior chambers in both eyes. Corneal topography showed more prominent spherical patterns and corneal flattening in the middle and extreme periphery. At the age of 5 years, he began to present recurrent ataxia, focal onset epileptic seizures of clonic motor in the right hemibody and vomiting. He was admitted in a coma in the pediatric intensive care unit of "William Soler" University Pediatric Hospital. Progressive encephalopathy was stated due to disorder in the urea cycle after hyperammonemia (congenital error of metabolism) was observed, without metabolic acidosis. Conclusions: Congenital flat cornea is a disease characterized by generalized corneal flattening with an impact on visual quality. Inborn errors of metabolism due to disorders in the urea cycle are characterized by severe neurological manifestations with potential danger to life. The presentation of these two rare diseases in the same patient is novel; an association that has not been published previously.

Amino Acids and Acylcarnitines Reference Values for Neonatal Screening of Inborn Errors of Metabolism in Colombia by Tandem Mass Spectrometry

Abstract Neonatal screening in Colombia has been carried out since 2000. The problem that most concerns is the absence of expanded screening. To stablish reference values for amino acids and acylcarnitines, in order to provide information to guide the implementation of expanded screening. Samples collected on Whatman 903 filter paper from 10284 newborns were processed by Tandem Mass Spectrometry System (Waters - Perkin Elmer), and the NeoBase™ non-derivatized MS/MS kit (PerkinElmer), which contains controls for 11 amino acids, and 31 acylcarnitine species. For each analyte the upper limit was set above the 99th percentile, while the lower limit was set below the 1st percentile. Comparison of full-term newborn amino acid concentrations with premature ones showed no significant differences in three of them: Glycine p-0.99574, Ornithine p=0.35274, Phenylalanine p=0.13499, neither in levels of 11 of the 31 acylcarnitines. Comparison of analyte concentrations in this study with previous reports showed significant differences for all amino acids and acylcarnitines (<0.05). Experience was gained in the pre-analytic stage of expanded screening and reference values were established, for the implementation of neonatal screening program in the country.

Renal replacement therapy in neonates with an inborn error of metabolism / 소아과

Hyperammonemia can be caused by several genetic inborn errors of metabolism including urea cycle defects, organic acidemias, fatty acid oxidation defects, and certain disorders of amino acid metabolism. High levels of ammonia are extremely neurotoxic, leading to astrocyte swelling, brain edema, coma, severe disability, and even death. Thus, emergency treatment for hyperammonemia must be initiated before a precise diagnosis is established. In neonates with hyperammonemia caused by an inborn error of metabolism, a few studies have suggested that peritoneal dialysis, intermittent hemodialysis, and continuous renal replacement therapy (RRT) are effective modalities for decreasing the plasma level of ammonia. In this review, we discuss the current literature related to the use of RRT for treating neonates with hyperammonemia caused by an inborn error of metabolism, including optimal prescriptions, prognosis, and outcomes. We also review the literature on new technologies and instrumentation for RRT in neonates

Analysis of CGDH gene variants and clinical features in three patients with glutaric aciduria type Ⅰ / 中华医学遗传学杂志

Objective@#To screen for potential variants of GCDH gene in 3 patients clinically diagnosed as glutaric aciduria type Ⅰ.@*Methods@#GCDH gene variants was detected by Sanger sequencing among the three children and their family members.@*Results@#Sanger sequencing showed that patient 1 carried compound heterozygosity variants of c. 532G>A (p.Gly178Arg) and c. 655G>A (p.Ala219Thr) of the GCDH gene, while his father and mother respectively carried heterozygous c. 532G>A(p.Gly178Arg) and c. 655G>A (p.Ala219Thr) variants. Patient 2 carried c. 532G>A (p.Gly178Arg) and a novel c. 1060G>T (p.Gly354Cys) compound heterozygous variant, while his father and mother respectively carried heterozygous c. 532G>A (p.Gly178Arg) and c. 1060G>T (p.Gly354Cys) variant. Patient 3 carried homozygous c. 532G>A (p.Gly178Arg) variant of the GCDH gene, for which both of his parents were heterozygous carriers.@*Conclusion@#The GCDH gene variant probably underlie the glutaric aciduria type Ⅰ among the 3 patients. Identifcation of the novel variant has enriched the spectrum of GCDH gene variants.

Analysis of inborn error metabolism in 277 children with autism spectrum disorders from Hainan / 中华医学遗传学杂志

Objective@#To assess the value of dry blood spot tandem mass spectrometry for the diagnosis of autism spectrum disorder (ASD).@*Methods@#Peripheral blood samples of 277 autistic children were collected. Their amino acid and carnitine profiles were detected by liquid chromatography tandem mass spectrometry. Urine samples of suspected patients were collected for verification by gas chromatography mass spectrometry. Blood samples were also taken for genetic testing.@*Results@#Of the 277 children with ASD, 19 (6.9%) were suspected to be with inborn error of metabolism (IEM), which included 6 cases with amino acidemia, 9 with organic acidemia and 4 with fatty acidemia. Three cases of phenylketonuria, one case of homocysteinemia, one case of propionemia, one case of methylmalonic acidemia, one case of glutaric acidemia, one case of isovaleric acidemia, one case of argininemia, one case of citrullinemia I and four cases of primary carnitine deficiency were confirmed by genetic testing, which yielded an overall diagnostic rate of 5.1% (14/277).@*Conclusion@#Our result has provided further evidence for the co-occurrence of ASD and IEM. Tandem mass spectrometry has a great value for the diagnosis and treatment of ASD in childhood.

Unignorable late-onset inborn errors of metabolism of the nervous system / 中华神经科杂志

Inborn errors of metabolism (IEMs) are defined as genetically enzymatic deficiencies or defects in polypeptide or protein involved in cellular metabolism,which include nearly a thousand kinds of genetic-definite disease entities up to now and could develop symptoms and signs at any age,and those whose onset-age is more than 1 years old are named as late-onset IEMs.More than 80％ of IEMs could involve the nervous system,also called IEMs of the nervous system,and most of the late-onset IEM patients will go to the Deparment of Neurology firstly.The treatment aim of IEMs is to correct the metabolic deficiency.The main therapeutic strategies include substrate-limitted intake,enzyme replacement therapy,clearance of the toxic metabolites,cofactor supplement,gene therapy and sympatomatic and support treatment.Many kinds of late-onset IEMs of the nervous system are treatable,and could be healthy living if treated early and correctly.Therefore,it is important to strengthen the understanding of neurologists on the late IEMs of the nervous system,which should not be ignored.

Ethylmalonic Encephalopathy in an Indian Boy.

Background: Ethylmalonic encephalopathy is a rare inborn error of metabolism characterized by neurodevelopmental delay / regression, recurrent petechiae, orthostatic acrocyanosis, and chronic diarrhea. Case Characteristics: 4-year-old boy with developmental regression, chronic diarrhea, petechial spots and acrocyanosis. MRI brain showed T2W/FLAIR hyperintensities in bilateral caudate and putamen. Abnormal acyl-carnitine profile and metabolites on urinary GC-MS analysis suggested the diagnosis. Intervention: Sequencing of ETHE1 gene revealed mutations: c.488G>A and c.375+5G>T (novel). Message: EE is clinically-recognizable disorder with typical clinical features.

Caracterización clínica, bioquímica e imagenológica en una cohorte de pacientes diagnosticados con hiperglicinemia no cetósica clásica: estudio ambispectivo 2000-2014, Medellín, Colombia / Clinical, biochemical and imaging characterization in a cohort of patients diagnosed with classical nonketotic hyperglycinemia: ambispective study 2000-2014, Medellin-Colombia

Introducción: La hiperglicinemia no cetósica (HGNC) es un error innato del metabolismo del grupo de las aminoacidopatías, de carácter autosómico recesivo, causado por un defecto en el sistema de clivaje de la glicina. Es una entidad rara y no se conoce su incidencia en Colombia. Objetivo: Describir características clínicas, bioquímica e imagenológicas en una cohorte de pacientes diagnosticados con hiperglicinemia no cetósica clásica Materiales y métodos: Estudio de tipo descriptivo, ambispectivo, en el periodo enero 2000-2014, en varios centros de Medellín. Resultados: Se incluyeron 20 pacientes que cumplían criterios de inclusión, de los 35 pacientes que cumplían con el criterio de búsqueda, en su mayoría de sexo femenino y con un Apgar adecuado al nacer. El promedio de inicio de los síntomas fue de 2,6 días; somnolencia, hipoactividad, apnea, convulsiones y singulto fueron los principales síntomas, y las convulsiones de tipo focal las más frecuentes. La relación glicina LCR/plasma en promedio fue 0,42. El patrón estallido-supresión en el electroencefalograma y la ausencia o retraso en la mielinización de la sustancia blanca supratentorial en la resonancia magnética fueron hallazgos comunes. Conclusión: La HGNC es frecuente en nuestro medio, por lo cual es necesario que se disponga de pruebas bioquímicas y moleculares necesarias para diagnóstico oportuno, manejo integral y asesoría genética.

Introduction: Nonketotic Hyperglycinemia is an inborn error of metabolism in a group of aminoacidopathies, autosomal recessive, caused by a defect in the system of the glycine cleavage. It is rare, and the incidence is unknown in Colombia. Objective:To describe clinical, biochemical and imaging characteristics in a cohort of patients diagnosed with classical nonketotic hyperglycinemia. Materials and methods: This is a descriptive-ambispective study during the period January 2000 - 2014 in some centers of Medellin. Results: There were 35 patients who met the search criteria and finally 20 patients who met inclusion criteria. We found in this cohort more girls than boys, and most of them with a good APGAR. The average onset of symptoms was 2.6 days, with drowsiness, hypoactivity, apnea, seizures and singultus the main symptoms. The focal seizures were the most frequent type. The average value of CSF glycine to plasma glycine ratio was 0.42. The burst suppression pattern in the EEG and the absence or delayed myelination in the supratentorial white matter on MRI were common findings. All patients received dextromethorphan as part of their treatment and the vast majority of sodium benzoate. Conclusion: HGNC is common in our environment. It´s necessary to have available biochemical and molecular evidence for timely diagnosis, comprehensive management and genetic counseling.

Actualización en el manejo agudo de errores congénitos del metabolismo / Update on acute management of inborn errors of metabolism

Inborn metabolic disorders are genetic diseases which are uncommon each one, but together they are not. They are characterized by an enzimatic defect that blocks a metabolic pathway, producing specific signs and symptoms. The current article pretends be an updated guideline for their acute management which is based on: 1) Inmediate life support, hydroelectrolyte balance and sample procurement, 2) Avoiding the production of toxic endogenous metabolites and anabolism promotion, 3) The supplementation of substrates and 4) The removal of toxic substances. Their prompt suspicious, identification and treatment starting will be crucial for neurological prognosis and prevention of death.

Los errores congénitos del metabolismo son enfermedades genéticas poco frecuentes pero que en conjunto no lo son. Se caracterizan por un defecto enzimático que bloquea una vía metabólica produciendo manifestaciones clínicas características. El objetivo del presente artículo es presentar una guía actualizada para su manejo agudo, el cual consiste en: 1) Medidas inmediatas de soporte vital, manejo hidroelectrolítico y obtención de muestras críticas; 2) Evitar la producción endógena de metabolitos tóxicos y favorecer el anabolismo; 3) Suplementación de sustratos y 4) Remoción de sustancias tóxicas. Su pronta sospecha, identificación e inicio de tratamiento, resulta fundamental para mejorar el pronóstico neurológico y evitar la muerte.

Present Status and Future Concerns of Expanded Newborn Screening in Malaysia: Sustainability, Challenges and Perspectives

Newborn screening (NBS) program is an important tool for the early diagnosis and preventive treatment of life-long impairments. NBS is one of the strategies recommended by the World Health Organization to promote the primary prevention of congenital anomalies and the health of children with these conditions. However, NBS initiation and implementation in developing countries, especially South-East Asian and North African regions, are slow and challenging. Expanded NBS is not mandatory and has not yet been incorporated into the public healthcare system in our country. Limited funding, manpower shortages, inadequate support services, low public awareness, and uncertain commitment from healthcare practitioners are the main challenges in establishing this program at the national level. Involvement and support from policy makers are very important to the success of the program and the benefit of the entire population.

Encefalopatía metabólica en acidemia isovalérica: Informe de caso / Metabolic encephalopathy in isovaleric academia: Case report

La acidemia isovalérica (AIV) es un trastorno congénito raro (prevalencia 1/105), herencia autosómica recesiva, en la vía metabólica de la leucina. Es causado por la deficiencia selectiva de la enzima mitocondrial isovaleril-CoA deshidrogenasa, la actividad reducida de esta enzima lleva a la acumulación tóxica del ácido isovalérico en el plasma y a un incremento en la concentración urinaria de isovalerilglicina. Han sido reportadas tres formas clínicas de presentación: aguda neonatal, crónica intermitente y una forma lentamente progresiva que puede ser asintomática. Caso clínico: Preescolar femenina de 3 años que ingresa a urgencias pediátricas por vómitos y somnolencia, sin déficit motor ni signos meníngeos; respiración profunda y rápida con olor particular. Historia negativa para trauma, infección o enfermedad metabólica definida. Citoquímica de líquido cefalorraquídeo normal; acidosis metabólica severa, hiperamonemia, disfunción hematológica y hepática motivaron el estudio metabólico, evidenciándose en orina Isovalerilglicina 38.290 mmol/mol creatinina, 3 OH Isovalérico, presente, 3 OH butírico 3.530 mmol/mol creatinina, orientando el diagnóstico a Acidemia Isovalérica. El diagnóstico de Acidemia Isovalérica debe considerarse ante la presencia de vómitos, deterioro neurológico progresivo y/o antecedentes familiares de muerte súbita neonatal. La posibilidad de evitar la mortalidad temprana y mejorar el resultado neurocognitivo por el diagnóstico y el tratamiento precoz favorece el diagnóstico preclínico y refuerza que la AIV sea incluida en el programa de cribado neonatal en Venezuela.

Isovaleric acidemia (IVA) is a rare autosomal recessive inborn error of leucine metabolism (prevalence 1/105) caused by a deficiency of the mitochondrial enzyme isovaleryl-CoA dehydrogenase resulting in the accumulation of derivatives of isovaleryl-CoA, the diminished activity of this enzyme leads to toxic accumulation of isovaleric acid in the plasma and an increase in urinary concentration of isovalerylglycine. There have been reported three clinical forms: acute neonatal form, a chronic intermittent form and a slowly progressive form which may be asymptomatic. Case report: We report the case of a 3 years old female with vomiting and drowsiness, sensorineural depression without motor deficit, no meningeal signs, CSF cytochemical normal, fast deep breathing and a "particular smell”, the presence of severe metabolic acidosis, hyperammonemia, hematologic and hepatic dysfunction motivated a metabolic study, showing in urine isovalerylglycine 38.290 mmol / molcreatinine, 3 OH isovaleric present, 3 OH butyric 3.530 mmol / molcreatinine, guiding the diagnosis to Isovaleric acidemia. The diagnosis of Isovaleric acidemia must be considered in the presence of vomiting, progressive neurological deterioration and / or family history of sudden infant death. The possibility of avoiding early mortality and improve neurocognitive outcome for diagnosis and early treatment promotes pre-symptomatic diagnosis and reinforces that IVA is included in the neonatal screening program in Venezuela.

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.

Annual Report on External Quality Assessment in Metabolic Disorders in Korea (2009) / 임상검사와정도관리

Two trials of external quality assessment for conventional newborn screening tests for phenylketonuria, congenital hypothyroidism, galactosemia, maple syrup urine disease and homocytinuria and for the newborn screening tests using tandem mass spectrometry (MS/MS) were performed in 2009. Total 20 specimens were distributed to 13 laboratories. All the control materials were send as dried blood spots. The response rate was 100%. The mean, SD, CV, median and range were analyzed. In addition, two trials of external quality assessment for glycohemoglobin (HbA1c) were performed in 2009. Total 6 samples were distributed to 196 laboratories and the response rate was 97.2% (175/180) and 98.5% (193/196) in each trial. From this trial, we performed accuracy-based survey which used challenge specimens that were free from matrix effects and had target values traceable to certified reference material. Bias between each participants result and reference target value were evaluated.

Sphingolipidoses of lysosomal storage disorders / 临床儿科杂志

Objective Sphingolipidoses are a group of rare genetic disorders caused by catabolism defect of sphingolipids by lysosomal hydrolases with diverse presentations,and represent an important health problem to almost all ethnic populations. To date,there is no epidemiologic study on the prevalence of sphinglipidoses,individually,or as a group,in China. We set up a series of enzymatic assays that could make definite diagnoses with the aim to collect data for an epidemiologic investigation of sphingolipidoses and also pave the way to prenatal diagnosis to decrease the rate of inborn error of metabolism. Methods Patients with suspected sphingolipidosis were recruited from pediatric endocrinology and inherited metabolism outpatient clinics of Xinhua Hospital. Leukocytes were isolated with dextran from peripheral bloods. Activities of leukocyte acid β-glucosidase,acid sphingomyelinase,arylsulphatase A,galacto-cerebrosidase,beta-galactosidase were measured using their specific artificial fluorescent substrates,while arylsulfatase A was determined by a colorimetric assay with dipotassium 2-hydroxy-5-nitrophenyl sulfate as the substrate. Results In one year,we identified 17 patients with 5 different kinds of sphingolipidoses,including 3 patients with Gaucher disease,9 patients with Niemann-Pick type A/B,2 patients with metachromatic leukodystrophy,2 patients with Krabbe disease,and 1 patient with GM1 gangliosidosis. We made brief descriptions of disease characters of each different kind disease and compared our results with findings of other ethnic groups. Conclusions Sphinglipidoses was markedly under-diagnosed in China and general pediatricians should be alerted to sphinglipidoses.

Annual Report on External Quality Assessment in Metabolic Disorders in Korea (2008) / 임상검사와정도관리

Two trials of external quality assessment for the newborn screening tests of inborn errors of metabolism including PKU screening, TSH, T4 (total/free), galactosemia screen, maple syrup urine disease screen and homocytinuria screen and newborn screening tests using tandem mass spectrometry were performed in 2008. Total 20 specimens for the newborn screening tests were distributed to 14 laboratories. The response rate was 100%. All the control materials were sent as dried blood spot forms. The mean, SD, CV, median and range were analyzed. The newborn screening tests using tandem mass spectrometry (MS/MS) were analyzed that the participants results for amino acids, acylcarnitine and their cutoff values. In addition, two trial of external quality assessment for glycohemoglobin (HbA1c) was performed in 2008. Total five samples were distributed to 238 laboratories and the response rate was 95.8% (228/238) and 97.4% (225/231), in each. Statistical data such as mean, SD and CV were provided for peer groups.

Annual Report on External Quality Assessment in Inborn Error of Metabolism in Korea (2005) / 임상검사와정도관리

The trial of external quality assessment for inborn error of metabolism was performed in 2005. Total 11 specimens for the conventional newborn screening tests were distributed to 47 laboratories. The response rates were 92.5% (37/40) and 100% (47/47), in each trial. All the control materials were sent as filter paper forms. Each laboratory replied the test results of the screening items that they were doing as a routine test at the reception of the specimen among PKU screening, TSH, T4 (total/free), galactosemia screen, maple syrup urine disease screen, homocystinuria screen and histidinemia screen. The mean, SD, CV, median and range were analyzed. The pilot proficiency test for newborn screening using tandem mass spectrometry (MS/MS) was also performed. Total 8 blood spots were distributed to 9 laboratories performing newborn screening using MS/MS. Participants' results for amino acids & acylcarnitine and their cutoff values were analyzed.

Annual Report on External Quality Assessment in Inborn Error of Metabolism in Korea (2004) / 임상검사와정도관리

The trial of external quality assessment for inborn error of metabolism was performed twice in 2004. Total 10 specimens for the conventional newborn screening tests were distributed to 43 laboratories. The response rates were 90.7%(39/43) in first trial and 90%(36/40) in second trial. All the control materials were sent as filter paper forms. Each laboratory replied the test results as the screening items they were doing as a routine test at the reception of the specimen among PKU screening, TSH, T4 (total/free), galactosemia screen, maple syrup urine disease screen, homocytinuria screen and histidinemia screen. The mean, SD, CV, median and range were analyzed. From this trial, pilot proficiency test for newborn screening using tandem mass spectrometry (MS/MS) was also performed. Total 8 blood spots were distributed to 7 laboratories performing newborn screening using MS/MS. Participants results for amino acids & acylcarnitine and their cutoff values were analyzed.