Two Libyan siblings with beta-ketothiolase deficiency: a case report and review of literature

Beta-ketothiolase [mitochondrial acetoacetyl-CoA thiolase, T2] deficiency is an autosomal recessive disorder characterized by impaired metabolism of ketones and isoleucine. In this study, we report on the first two siblings with T2 deficiency from Libya. Both siblings presented with ketoacidosis, but the severity and outcomes were quite distinctive. T2 deficiency in patient 1, the younger sister, manifested as recurrent severe episodes of ketoacidosis during the first year of life. She unfortunately experienced neu-rodevelopmental complications, and died at 14 months old, after her 5th episode. In contrast, patient 2, the elder brother, experienced only one ketoacidotic episode at the age of 4 years. He recovered uneventfully and has continued to achieve age-appropriate development to date. Upon analysis, the siblings' blood acylcarnitine profiles had shown increased levels of C5:l and C5-OH carnitine. ACAT1 mutational analysis revealed patient 2 is homozygotic for a novel mutation-c.674C > A [p.Ala225Glu]; this mutation was then confirmed by familial analysis. Transient expression analysis of C.674C > A mutant T2 cDNA revealed neither potassium ion-activated acetoacetyl-CoA thiolase activity, which represents T2 activity, nor mutant T2 protein. Therefore, this mutation is truly pathogenic. Interestingly, the incidence of T2 deficiency may be high among the Arab population. This disease should be considered in the differential diagnosis for unexplained ketoacidosis in children. Patients with T2 deficiency could have a favorable outcome if diagnosed and treated early

Expression of non-neuronal cholinergic system in maxilla of rat in vivo

BACKGROUND: Acetylcholine (ACh) is known to be a key neurotransmitter in the central and peripheral nervous systems, which is also produced in a variety of non-neuronal tissues and cell. The existence of ACh in maxilla in vivo and potential regulation role for osteogenesis need further study. RESULTS: Components of the cholinergic system (ACh, esterase, choline acetyltransferase, high-affinity choline uptake, n- and mAChRs) were determined in maxilla of rat in vivo, by means of Real-Time PCR and immunohistochemistry. Results showed RNA for CarAT, carnitine/acylcarnitine translocase member 20 (Slc25a20), VAChT, OCTN2, OCT1, OCT3, organic cation transporter member 4 (Slc22a4), AChE, BChE, nAChR subunits α1, α2, α3, α5, α7, α10, ß1, ß2, ß4, γ and mAChR subunits M1, M2, M3, M4, M5 were detected in rat's maxilla. RNA of VAChT, AChE, nAChR subunits α2, ß1, ß4 and mAChR subunits M4 had abundant expression (2(-ΔCt) > 0.03). Immunohistochemical staining was conducted for ACh, VAChT, nAChRα7 and AChE. ACh was expressed in mesenchymal cells, chondroblast, bone and cartilage matrix and bone marrow cells, The VAChT expression was very extensively while ACh receptor α7 was strongly expressed in newly formed bone matrix of endochondral and bone marrow ossification, AchE was found only in mesenchymal stem cells, cartilage and bone marrow cells. CONCLUSIONS: ACh might exert its effect on the endochondral and bone marrow ossification, and bone matrix mineralization in maxilla.

O uso da L-carnitina como adjuvante no tratamento da miocardiopatia dilatada em criança com Aids / Usage of L-carnitine as adjuvant in the treatment of dilated cardiomyopathy in a child with Aids

OBJETIVO: Apresentar a resposta cardiovascular à L-carnitina de um paciente com insuficiência cardíaca congestiva decorrente de miocardiopatia dilatada pelo vírus da imunodeficiência humana. DESCRIÇÃO DO CASO: Criança com quadro clínico de insuficiência cardíaca congestiva grave devido à miocardiopatia dilatada pela síndrome de imunodeficiência adquirida. O tratamento para as manifestações clínicas foi instituído, com pouca resposta clínica. Com objetivo de melhorar o desempenho energético/metabólico dos cardiomiócitos, foi instituída terapia com L-carnitina. Observou-se significativa melhora clínica do paciente, em relação ao desempenho cardíaco, mesmo antes do início do tratamento com os fármacos antirretrovirais. COMENTÁRIOS: A L-carnitina é um composto que facilita o transporte dos ácidos graxos de cadeia longa para dentro da mitocôndria. Nesse caso, o uso da L-carnitina parece ser clinica e bioquimicamente justificado.

OBJECTIVE: To present the cardiovascular response to L-carnitine of a patient with congestive heart failure caused by dilated cardiomyopathy and human immunodeficiency virus. CASE DESCRIPTION: Child with a clinical history of severe congestive heart failure due to dilated cardiomyopathy caused by acquired immunodeficiency syndrome. The treatment for the symptoms resulted in a poor clinical response. In order to improve the energetic performance/metabolism of cardiomyocytes, therapy with L-carnitine was established. There was significant clinical improvement of the cardiac performance of the patient, even before starting the treatment with antiretroviral drugs. COMMENTS: L-carnitine is a compound that facilitates the transport of long-chain fatty acids into the mitochondria. In this case the administration of L-carnitine appears to be clinically and biochemical justified.

Newborn screening--is it really that simple?

The incorporation of tandem mass spectrometry (MSMS) into an existing newborn screening program is an evolving process. Limited worldwide experience has ensured that all stages of reliability testing need to be followed. These include a literature review to establish methodology and analytes/disorders for testing and a pilot screening project including assaying archival samples from subjects with proven target disorders. Algorithms used for analyte concentrations and the relationships of various analytes to one another for resample criteria need to be continually reassessed to maximise screening specificity, sensitivity and positive predictive value. Since 1st of April 1998, the NSW Newborn Screening Program has screened 320, 848 babies using electrospray MSMS for selected amino acids and acyl camitines. Screening for amino acids has led to requests for 415 repeat samples with 94 babies referred for further testing. Of these 73 had a disorder of amino acid metabolism, including 43 with persistent hyperphenylalaninemia (36 of whom had PKU, 2 had a pterin pathway defect, 5 HPAA). Screening for acyl carnitines has led to requests for 245 repeat samples with 63 babies referred for further investigation. Of these 44 had a diagnosed disorder, including 15 with medium chain acyl CoA dehydrogenase deficiency. Five babies with confirmed disorders detectable with MS/MS had negative test results. The cost of screening using MSMS was only $A0.50 more than the method for screening for PKU and homocystinuria alone (ie the bacterial inhibition assays) and has allowed detection of an additional 74 babies at least 48 of whom have a diagnosis for which early treatment seems clearly beneficial. MSMS has shown a sensitivity of 95.9% and specificity of 99.8% in our laboratory with a positive predictive value of 18%.

Detection of inherited metabolic disorders via tandem mass spectrometry in Thai infants.

From a retrospective study in Medical Genetics Unit, Department of Pediatrics, Siriraj Hospital Faculty of Medicine, Mahidol University in Bangkok (1983-1988), the estimated pediatric patients with clinically suspected IEM are approximately 2-4% of total annual pediatrics admission of 5,000 or more. This is, a low estimation since survey from all teaching hospitals in the country including the largest Children's Hospital in Bangkok indicated the presence of numerous IEM. However, most IEM were clinically diagnosed with limited laboratory facilities. We started a collaboration with Magee Womens Hospital of Pittsburgh and NeoGen Screening, USA; using tandem mass spectrometry to diagnose high risk infants and children for IEM from July 1993 to March 1998. Of total 146 samples sent, we detected numerous metabolic disorders (11.2%) eg phenylketonuria, organic acidemia, maple syrup urine disease, isovaleric acidemia, methylmalonic acidemia, albinism, translocase/carnitine palmitoyltransferase type II, G6PD deficiency and lysinuric protein intolerance.

Detección de deficiencia de acil CoA dehidrogenasa de cadena media a través de un programa de pesquisa neonatal en la Argentina / Medium chain acyl CoA dehidrogenase deficiency detected with a neonatal screening program

La deficiencia de acil-CoA-dehidrogenasa de cadena media (MCADD) es una de las enfermedades metabólicas congénitas (EMC) más frecuentes. Este trastorno de la ß-oxidación de los ácidos grasos se presenta generalmente en lactantes mayores de 6 meses. Las manifestaciones clínicas características son vómitos, letargo, hipotonía y leve hepatomegalia. El laboratorio revela hipoglucemia, hipocetosis, aumento moderado de las transaminasas y amonio y leve acidosis metabólica. El episodio es generalmente desencadenado por un ayuno prolongado o una enfermedad intercurrente. En un 18 por ciento de los casos la MCADD se manifiesta por primera vez con muerte súbita, la mortalidad total es de 24 por ciento y las secuelas de los pacientes que sobreviven pueden ser severas. La pesquisa neonatal de EMC es uno de los pilares de la medicina preventiva. Las enfermedades más comúnmente buscadas son la fenilcetonuria y el hipotiroidismo congénito, pero existen programas de pesquisa que abarcan otras EMC: como galactosemia, leucinosis o deficiencia de biotinidasa. La incorporación de una nueva tecnología, la espectrometría de masa en tándem (EMT), que permite la detección simultánea de 20 enfermedades, ha permitido incluir a los trastornos de la ß-oxidación dentro del grupo de patologías pasibles de detección neonatal. En el presente trabajo reportamos el primer caso de MCADD detectado por EMT en un programa de pesquisa neonatal en Argentina. Se presenta un niño RNT-PAEG con examen físico normal. La muestra de sangre fue obtenida a las 48 horas de vida con el paciente asintomático. El análisis se realizó en la Fundación para el Estudio de las Enfermedades Neurometabólicas (FESEN) como parte del programa de pesquisa neonatal por EMT. De la sangre impregnada en el papel de filtro se prepararon los éteres butílicos de acilcarnitinas y aminoácidos. La detección de las acilcarnitinas se realizó por EMT con un equipo VG Quatro II MS-MS (Micromass, Reino Unido) mediante el barrido de iones precursores de m/z 85. Los valores normales fueron obtenidos en una población de 400 recién nacidos sanos estudiados con la misma metodología. Como control patológico se analizó una muestra de una paciente con MCADD en tratamiento, diagnosticada en ocasión de presentarse con un síndrome de Reye. En el paciente se halló un marcado aumento de octanoilcarnitina (C8): 7,92 µM, con un menor aumento de hexacoilcarnitina (C6): 1,31 µM y decanoilcarnitina: 0,87 µM