1/23. Atypical nonketotic hyperglycinemia with normal cerebrospinal fluid to plasma glycine ratio.The diagnosis of nonketotic hyperglycinemia is considered to depend upon the presence of increased cerebrospinal fluid glycine and an increased cerebrospinal fluid to plasma glycine ratio. We studied two siblings who have the neurologic and peripheral biochemical features of the atypical variant of nonketotic hyperglycinemia but have normal cerebrospinal fluid glycine and cerebrospinal fluid to plasma glycine ratios. The proband had reduced liver glycine cleavage system activity of 17% and 21% of mean normal values, confirmed in two independent laboratories. Her lymphoblast glycine cleavage system activity was normal. Nonketotic hyperglycinemia can be present in the absence of increased cerebrospinal fluid glycine. Measurement of liver glycine cleavage system activity is indicated when nonketotic hyperglycinemia is suggested by clinical features and peripheral glycine levels but cerebrospinal fluid glycine is normal.- - - - - - - - - - ranking = 1keywords = hyperglycinemia (Clic here for more details about this article) |
2/23. Acute hydrocephalus in nonketotic hyperglycemia.We present four patients with typical neonatal onset non-ketotic hyperglycinemia (NKH) who developed hydrocephalus requiring shunting in early infancy. Brain imaging revealed acute hydrocephalus, a megacisterna magna or posterior fossa cyst, pronounced atrophy of the white matter, and an extremely thin corpus callosum in all. The three older patients had profound developmental disabilities. This suggests that the development of hydrocephalus in NKH is an additional poor prognostic sign.- - - - - - - - - - ranking = 0.125keywords = hyperglycinemia (Clic here for more details about this article) |
3/23. Transient nonketotic hyperglycinemia in an asphyxiated patient with pyridoxine-dependent seizures.An asphyxiated neonate with pyridoxine-dependent seizures and associated transient nonketotic hyperglycinemia is reported. Frequent seizures and their resultant hypoxic-ischemic insult may have led to the elevation of the cerebrospinal fluid glycine level in this patient. early diagnosis and treatment of pyridoxine-dependent seizures is essential for an improved neurologic outcome.- - - - - - - - - - ranking = 0.625keywords = hyperglycinemia (Clic here for more details about this article) |
4/23. Human glycine decarboxylase gene (GLDC) and its highly conserved processed pseudogene (psiGLDC): their structure and expression, and the identification of a large deletion in a family with nonketotic hyperglycinemia.Mutations in the glycine decarboxylase gene (GLDC) cause nonketotic hyperglycinemia (NKH), an in-born error of metabolism characterized by severe neurological disturbance. We have determined the structure of GLDC and of its pseudogene (psiGLDC) and studied their expression for a molecular analysis of NKH. The GLDC gene spans at least 135 kb and consists of 25 exons. All donor and acceptor sites adhere to the canonical GT-AG rule, except for the donor site of intron 21, where a variant form GC is used instead of GT. The transcription initiation site has been assigned to a residue 163 bp upstream from the translation initiation triplet by primer extension analysis. The psiGLDC gene has no intron and shares 97.5% homology with the coding region of functional GLDC, suggesting that psiGLDC is a processed pseudogene that arose from the GLDC transcript about 4-8 million years ago. RNA blotting analysis has revealed that GLDC is expressed in human liver, kidney, brain, and placenta. We have also examined a patient with NKH with no detectable GLDC mRNA in his lymphoblasts. exons 1-3 of the functional GLDC gene from this patient are not amplified by polymerase chain reaction (PCR), whereas those from control subjects are. These results suggest a large homozygous deletion (at least 30 kb) in the patient. Furthermore, we have devised a semi-quantitative PCR to estimate the number of GLDC alleles by using psiGLDC as an internal control and have confirmed the homozygosity and heterozygosity of the deletion in the patient and his parents, respectively. Structural information of GLDC and psiGLDC should facilitate the molecular analysis of NKH.- - - - - - - - - - ranking = 0.625keywords = hyperglycinemia (Clic here for more details about this article) |
5/23. acrodermatitis enteropathica-like eruption in an infant with nonketotic hyperglycinemia.acrodermatitis enteropathica is a rare inherited disorder characterized by zinc deficiency and a triad of dermatitis, diarrhea, and alopecia. It is an autosomal recessive condition thought to be due to the inability to absorb zinc from the gastrointestinal tract. Acquired zinc deficiency due to a variety of etiologies may produce a similar clinical picture. These causes include inadequate supply, malabsorption, and low zinc stores. In addition to zinc, deficiencies of other nutrients such as branched chain amino acids have induced an acrodermatitis enteropathica-like eruption. We describe a case of a 26-month-old boy with a rare inborn error of metabolism known as nonketotic hyperglycinemia who developed an acrodermatitis enteropathica-like eruption. In addition to zinc deficiency, the patient was deficient in branched chain amino acids due to a low protein diet instituted to reduce his elevated glycine levels. The rash did not respond to zinc replacement alone, and therefore is most likely a combination of amino acid and zinc deficiency. acrodermatitis enteropathica-like eruptions have been described in other conditions that cause decreased serum amino acids, such as maple syrup urine disease and organic acidurias. This is the first case describing an association between acrodermatitis enteropathica and nonketotic hyperglycinemia.- - - - - - - - - - ranking = 0.75000006390061keywords = hyperglycinemia, deficiency (Clic here for more details about this article) |
6/23. In vivo 1H magnetic resonance spectroscopic measurement of brain glycine levels in nonketotic hyperglycinemia.Nonketotic hyperglycinemia (NKH) is an autosomal recessive disorder of glycine metabolism. Defective glycine cleavage causes elevated concentrations of glycine in plasma, urine, and cerebrospinal fluid. A longitudinal study using magnetic resonance imaging (MRI) and single-voxel 1H magnetic resonance spectroscopy (MRS) was performed on an infant with the typical clinical picture of NKH. He was examined twice during the course of treatment with sodium benzoate and dextromethorphan. At the age of 10 months, MRI showed normal brain structure, while MRS detected a prominent glycine peak in the brain. Repeat MRS at the age of 13 months showed a small increase in glycine peak and a prominent glutamate/glutamine peak not previously detected. The MRS measurements were consistent with the slight increase in blood glycine level and the elevation in glutamine level, indicating that 1HMRS can be a valuable tool in the diagnosis and monitoring of treatment effects in patients with NKH.- - - - - - - - - - ranking = 0.625keywords = hyperglycinemia (Clic here for more details about this article) |
7/23. Localized proton MR spectroscopic detection of nonketotic hyperglycinemia in an infant.Nonketotic hyperglycinemia (NKH) is a rare metabolic brain disease caused by deficient activity of the glycine cleavage system. Localized proton MR spectroscopy (echo-time 166 msec), performed in an infant with the typical clinical and biochemical features of neonatal NKH, showed a markedly increased peak intensity at 3.55 ppm, which was assigned to glycine. Serial proton MR spectroscopic studies indicated that glycine/choline and glycine/total creatine ratios correlated closely with the patient's clinical course. Proton MR spectroscopy was useful for the non-invasive detection and monitoring of cerebral glycine levels in this infant with NKH.- - - - - - - - - - ranking = 0.625keywords = hyperglycinemia (Clic here for more details about this article) |
8/23. prenatal diagnosis of hypoplasia of the corpus callosum in association with non-ketotic hyperglycinemia.Abnormalities of the corpus callosum are often associated with a poor prognosis due to the anatomical defect itself and associated anomalies that include malformations and inherited metabolic disorders. We report a case of the prenatal diagnosis of hypoplasia of the corpus callosum that was associated with non-ketotic hyperglycinemia. Metabolic disorders are a known association with corpus callosum abnormalities and carry a dismal prognosis. A diagnosis of non-ketotic hyperglycinemia should be considered when a fetus presents with an abnormality of the corpus callosum. A literature search reviews other inherited diseases associated with hypoplasia of the corpus callosum.- - - - - - - - - - ranking = 0.75keywords = hyperglycinemia (Clic here for more details about this article) |
9/23. Transient nonketotic hyperglycinemia: two case reports and literature review.Transient nonketotic hyperglycinemia is characterized by clinical and biochemical findings similar to those seen in classic nonketotic hyperglycinemia. Abnormalities in amino acids are partially or completely resolved in a period ranging from days to months. Almost all patients with the classic form of nonketotic hyperglycinemia survive with severe neurologic sequela, whereas most of the patients with the transient form exhibit normal development. Therefore, distinguishing the transient form of nonketotic hyperglycinemia from classic nonketotic hyperglycinemia is important to predict outcome of the patients.Transient nonketotic hyperglycinemia has been reported in only seven neonates. This article adds two cases to the transient nonketotic hyperglycinemia and reviews the relevant literature. Common clinical features were determined, and presence of miotic pupils was stressed.- - - - - - - - - - ranking = 1.375keywords = hyperglycinemia (Clic here for more details about this article) |
10/23. diffusion-weighted MR imaging in neonatal nonketotic hyperglycinemia.To our knowledge, we are the first to report the diffusion-weighted MR imaging findings in a 15-day-old neonate with nonketotic hyperglycinemia. We found bilaterally symmetrical lesions of restricted diffusion in the dorsal brain stem, cerebral peduncles, and posterior limbs of the internal capsule, which were more conspicuous and extensive on diffusion-weighted MR images than on T2-weighted images. These lesions are in the myelinated tracts of the neonate and are compatible with the expected sites of abnormality in vacuolating myelinopathy.- - - - - - - - - - ranking = 0.625keywords = hyperglycinemia (Clic here for more details about this article) |
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