1/22. 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.- - - - - - - - - - ranking = 1keywords = metabolic disorder (Clic here for more details about this article) |
2/22. Diffusion-weighted MRI of maple syrup urine disease encephalopathy.We report the case of a newborn child with maple syrup urine disease (MSUD), diagnosed at 10 days of life. Diffusion-weighted echoplanar MRI showed marked hyperintensity of the cerebellar white matter, the brainstem, the cerebral peduncles, the thalami, the dorsal limb of the internal capsule and the centrum semiovale, while conventional dual-echo sequence evidenced only a weak diffuse T2 hyperintensity in the cerebellar white matter and in the dorsal brainstem. The apparent diffusion coefficient (ADC) of these regions was markedly (>80%) decreased. Therefore, in agreement with current hypotheses on MSUD pathogenesis, MSUD oedema proves to be a cytotoxic oedema. Diffusion-weighted MRI may be a valuable tool, more sensitive than conventional spin-echo techniques, to assess the extent and progression of cytotoxicity in MSUD, as well as the effectiveness of the therapeutic interventions.- - - - - - - - - - ranking = 4.7195384393403E-5keywords = brain (Clic here for more details about this article) |
3/22. diffusion magnetic resonance imaging in intermediate form of maple syrup urine disease.An 8-year-old boy with the intermediate variant of maple syrup urine disease is reported. On b = 1000 s/mm2 (heavily diffusion weighted) images of diffusion magnetic resonance imaging, there was symmetric high signal in the globus pallidus, mesencephalon, dorsal pons, and nucleus dentatus, consistent with restriction of the mobility of water molecules. Apparent diffusion coefficient (ADC) maps revealed low ADC values ranging from 0.42 to 0.56 x 10(-3) mm2/s in these regions, compared to those of apparently unaffected regions in the brain parenchyma ranging from 0.63 to 0.97 x 10(-3) mm2/s. It is suggested that the areas of increased signal (and low ADC values) are the result of dysmyelination as a reflection of disorganized tissue integrity.- - - - - - - - - - ranking = 2.3597692196702E-5keywords = brain (Clic here for more details about this article) |
4/22. water apparent diffusion coefficient and T2 changes in the acute stage of maple syrup urine disease: evidence of intramyelinic and vasogenic-interstitial edema.BACKGROUND: The acute phase of the neonatal classical form of maple syrup urine disease (MSUD) is usually associated with generalized brain edema. methods AND RESULTS: The authors present the case of a newborn infant in the acute stage of the classical form of MSUD in whom a remarkable decrease in the water apparent diffusion coefficient (ADC) in advanced myelinating white matter areas was associated with an increase in the T2 signal. This diffusion magnetic resonance imaging (MRI) pattern appears to be compatible with a rare kind of cytotoxic edema, the so-called intramyelinic edema. At the same time, an increase in the ADC was seen in unmyelinated areas together with an increase in the T2 signal, a sign of a coexistent vasogenic-interstitial edema. CONCLUSIONS: ADC measurements in MSUD provide more specific information than conventional MRI about the pathophysiology of white matter changes.- - - - - - - - - - ranking = 2.3597692196702E-5keywords = brain (Clic here for more details about this article) |
5/22. maple syrup urine disease encephalopathy: a follow-up study in the acute stage using diffusion-weighted MRI.Neonatal maple syrup urine disease (MSUD) is associated with diffuse oedema and characteristic MSUD oedema. We present a newborn infant with two coexisting different types of oedema. The myelinated white matter showed a marked decrease in the water apparent diffusion coefficient (ADC) compatible with cytotoxic oedema. The unmyelinated white matter showed an increase in ADC, consistent with vasogenic-interstitial oedema. On follow-up studies, the cytotoxic oedema showed improvement, but the vasogenic-interstitial oedema progressed into brain atrophy.- - - - - - - - - - ranking = 2.3597692196702E-5keywords = brain (Clic here for more details about this article) |
6/22. maple syrup urine disease: diffusion-weighted and diffusion-tensor magnetic resonance imaging findings.We present conventional magnetic resonance (MR) imaging with diffusion-weighted and diffusion-tensor imaging findings in a 10-day-old neonate with maple syrup urine disease (MSUD). On conventional MR imaging, signal abnormalities were noted in the affected white matter of cerebellum, dorsal brainstem, thalami, posterior limbs of internal capsules, and the corona radiata. These regions showed marked hyperintensity on diffusion-weighted images with decreased apparent diffusion coefficient values (average 68% reduction). Diffusion-tensor imaging showed decreased anisotropy (average 57% reduction) in the corresponding areas. Both diffusion-weighted and diffusion-tensor imaging are valuable in the diagnosis and understanding of the pathogenesis of MSUD, with findings that suggest cytotoxic edema and damaged oligodendro-axonal units within the affected white matter.- - - - - - - - - - ranking = 2.3597692196702E-5keywords = brain (Clic here for more details about this article) |
7/22. Changes in the auditory nerve brainstem evoked responses in a case of maple syrup urine disease.maple syrup urine disease (MSUD) is a rare metabolic disease due to deficiency in the enzyme that breaks down branched chain amino acids. Lack of the enzyme causes accumulation of these amino acids and, if untreated, causes severe neurological damage. A case study of a 10-day old female infant, born after 40 weeks' gestation with a birthweight of 2740 g with MSUD hospitalized in the acute stage with respiratory failure and severe brain oedema is described. As part of the neurological evaluation, auditory nerve brainstem evoked response testing was conducted and revealed bilateral presence of the first wave from the auditory nerve, with no later brainstem waves. Over the course of days when her condition improved following dialysis treatment and a diet to reach balanced levels of branched chain amino acids, the later brainstem waves appeared on one side, and several weeks later they were also observed on the other side. The possible mechanisms of the reversibility of the appearance of brainstem waves in this case are discussed.- - - - - - - - - - ranking = 0.00021237922977032keywords = brain (Clic here for more details about this article) |
8/22. Computed tomography in maple syrup urine disease.maple syrup urine disease (MSUD) is an inherited metabolic disorder characterized by a severe, usually lethal, neonatal course in the early stages with pseudotumor cerebri and pathologically documented increased cerebral water content. CT and MRI studies in MSUD are few and the data are overlapping. This study reports CT features before and after dietary treatment in three patients; two with classical MSUD and one with an intermediate variant of MSUD. At diagnosis, CT consistently showed evidence of abnormally high lucidity involving not only white matter, but also areas of grey matter, particularly the pallidum. Furthermore, these CT changes are present both in the acute phase of classical MSUD and in an intermediate variant of the disease. The observed abnormalities evolve favorably under dietary treatment, simultaneously with clinical and neurological improvement. It is concluded that the observed CT changes indicate a diagnosis of MSUD and are relevant findings in the neuroradiologic differential diagnosis in acutely ill newborns, in which a metabolic disease may be not immediately suspected.- - - - - - - - - - ranking = 0.2keywords = metabolic disorder (Clic here for more details about this article) |
9/22. Diagnosis of MSUD by newborn screening allows early intervention without extraneous detoxification.maple syrup urine disease (MSUD) is a genetic metabolic disorder resulting from the defective activity of branched-chain 2-ketoacid dehydrogenase complex. Due to the metabolic block, high concentrations of the branched-chain amino acids (BCAA) leucine, valine, isoleucine, and allo-isoleucine as well as their corresponding branched-chain 2-keto acids accumulate in patients on a BCAA-unrestricted diet or during episodes with increased protein catabolism. early diagnosis and management are essential to prevent permanent brain damage. Newborn screening by tandem MS allows for detection of elevated BCAA concentrations in blood in patients with classical MSUD before they show severe encephalopathic symptoms. Here, we report that newborn screening by expanded tandem MS enables for reversing the intoxication in newborns with MSUD within 24-48 h without any need for extraneous detoxification and thus decreasing the risk of brain damage during a particularly vulnerable period.- - - - - - - - - - ranking = 0.20004719538439keywords = metabolic disorder, brain (Clic here for more details about this article) |
10/22. Abnormal dendritic development in maple syrup urine disease.The neuropathology of a 6-year-old boy with maple syrup urine disease revealed spongy appearance of the white matter and marked edema of the brainstem. Golgi studies demonstrated aberrant orientation of neurons together with abnormalities of dendrites and dendritic spines. Similar changes were observed in a patient with dihydropteridine reductase deficiency. Disorders of amino acid metabolism may be associated with alterations in the terminal stages of neuronal migration and maturation.- - - - - - - - - - ranking = 2.3597692196702E-5keywords = brain (Clic here for more details about this article) |
| | Next -> |