1/9. Aplasia of the retinal vessels combined with optic nerve hypoplasia, neonatal epileptic seizures, and lactic acidosis due to mitochondrial complex I deficiency.A newborn male with mitochondrial complex I deficiency suffered from neonatal epileptic seizures, which later developed into infantile spasms. The infant was blind due to aplasia of the retinal vessels and hypoplasia of the optic nerve. There was congenital lactic acidosis, which persisted in later life. The boy was microcephalic and retarded. Muscular hypotonia later shifted to spasticity. succinic acid was increased in urine. We assume that the aplasia of the retinal vessels is due to damage of the retinal ganglion cells caused by the mitochondrial disease in the first 3 to 4 months of pregnancy.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
2/9. central nervous system changes in mitochondrial encephalomyopathy: light and electron microscopic study.An autopsy case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) is reported. It presented with generalized muscle atrophy, stroke-like episodes, schizophrenia-like mental disorder and progressive dementia. serum lactate and pyruvate levels were high. In the biopsied muscles, ragged-red fibers were observed by light microscopy and aggregation of abnormal mitochondria with paracrystaline formation by electron microscopy. The most characteristic neuropathological findings were infarct-like lesions widespread in the cerebral cortex. In addition, this case showed some unusual pathological features: (1) diffuse moderate fibrillary gliosis in the whole cerebral and cerebellar white matter, which might have been due to metabolic disturbances; (2) several focal lesions with demyelination and numerous spheroids in the pontocerebellar fibers; and (3) marked degeneration of the posterior columns and spinocerebellar tracts. Electron microscopic examination revealed that abnormal mitochondria were markedly aggregated in smooth muscle cells and endothelium of the cerebral and cerebellar blood vessels. These fine structural findings suggest a "mitochondrial angiopathy".- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
3/9. MELAS of infantile onset: mitochondrial angiopathy or cytopathy?An 83-day-old male infant had convulsions, hypertrophic cardiomyopathy, and lactic acidosis. Cranial computed tomography revealed low-density areas in both parieto-occipital lobes and in the left temporal lobe. Muscle biopsy did not reveal ragged-red fibers, but abnormal mitochondria were found in the capillary endothelial cells as well as in the muscle fibers. At 5 months of age, the patient developed purpura on the soles and palms. skin biopsy showed degeneration of the endothelial cells with abnormal mitochondria in the arterioles and capillaries. Myelinated nerves in the skin had vacuolated axons with swollen mitochondria, and their myelin sheaths showed vacuolation. At 9 months of age, he died of heart failure, and autopsy revealed abnormal mitochondria in the myocardium but not in the coronary vessels. Our findings indicate that the symptoms of the mitochondrial encephalopathy, myopathy, lactic acidosis, and strokelike episodes (MELAS) syndrome cannot be fully explained by the mitochondrial angiopathy alone.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
4/9. Accidental and intentional poisonings with ethylene glycol in infancy: diagnostic clues and management.ethylene glycol has long been recognized as a potentially lethal poison and remains available today as automotive antifreeze and windshield deicer fluids. ethylene glycol is rapidly absorbed from the gastrointestinal tract, with peak levels measured one to four hours after ingestion. metabolism of the parent compound and the production of several organic acids are responsible for the metabolic acidosis observed in ethylene glycol poisoning. Target organ cellular damage is seen in the kidney, brain, myocardium, pancreas, and blood vessel walls. Renal tubular deposition of calcium oxalate crystals is felt to be responsible for the development of the severe renal injury which may accompany ethylene glycol ingestion. The clinical course is quite varied and includes inebriation, hematuria, cardiorespiratory compromise, and neurologic effects. Prompt diagnosis and initiation of treatment, including ethanol therapy and hemodialysis, is necessary to ameliorate the effects of ethylene glycol ingestion. Two cases of ethylene glycol poisoning, one accidental and one intentional, are reviewed.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
5/9. CT, MRI, and autopsy findings in brain of a patient with MELAS.brain autopsy findings in a 14-year-old patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes were compared with those of computed tomography (CT) and magnetic resonance imaging (MRI). Pathologic examinations revealed extensive laminar necrosis bordered by gliotic tissues throughout the cerebral cortices. Moderate losses of myelin and fibrous gliosis were also observed in the subcortical and deep white matter. These lesions were demonstrated as low-density areas on CT and as high-signal areas on T2-weighted MRI. MRI revealed the lesions more distinctively and precisely than CT. Neither CT nor MRI could reveal abnormalities in the basal ganglia, including vascular proliferation and calcium deposits in the blood vessels.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
6/9. Mitochondrial encephalomyopathy. A variant with heart failure and liver steatosis.We report the clinical and autopsy findings in a young man of 18 with a chronic progressive disorder comprised of lactic acidosis, mental deterioration, and epileptic seizures which were sometimes accompanied by stroke-like episodes with transient hemiparesis and cortical blindness. He died of congestive heart failure. The autopsy showed lesions of the gray matter of the brain. Both the putamen and parieto-occipital cortex showed loss of neurons and proliferation of macrophages, astrocytes and vessels. There was marked loss of neurons in the inferior olives, and slight reduction of the number of purkinje cells. Skeletal muscle studies revealed ragged-red fibers and structurally abnormal mitochondria. The heart was enlarged: accumulations of mitochondria occurred in the muscle fibers. The liver exhibited marked fatty degeneration. Biochemical analyses showed normal activities of pyruvate dehydrogenase in thrombocytes, pyruvate carboxylase in lymphocytes, biotinidase in serum as well as succinate dehydrogenase and cytochrome c oxidase. The features of this disorder differ in many respects from cases of mitochondrial encephalomyopathy previously reported and cannot be assigned to any specific disease entity.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
7/9. A MERRF/MELAS overlap syndrome associated with a new point mutation in the mitochondrial dna tRNA(Lys) gene.Several members of a three-generation kindred from Sardinia were affected by a maternally inherited syndrome characterized by features of both myoclonus epilepsy with ragged-red fibers (MERRF) and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). Clinically, symptoms such as myoclonus epilepsy, neural deafness and ataxia were variably associated with stroke-like episodes and/or migrainous attacks. Morphologically, numerous MELAS-associated SDH-stained vessels were observed in muscle biopsies, either alone or in combination with ragged-red fibers, the morphological hallmark of MERRF. sequence analysis of the mtDNA tRNA genes revealed the presence of a single, heteroplasmic T-->C transition at nt 8356, in the region of the tRNA(Lys) gene corresponding to the T-psi-C stem. The T-->C(8356) transition was exclusively found in the maternal lineage of our family, and the relative amount of the mutant mtDNA species in muscle was correlated with the severity of the clinical presentation. Therefore, we propose that the T-->C(8356) transition is responsible for the mitochondrial encephalomyopathy found in our family, and must be added to the expanding list of the pathogenetically relevant mutations of human mtDNA.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
8/9. Neuropathological findings of a patient with pyruvate dehydrogenase E1 alpha deficiency presenting as a cerebral lactic acidosis.Neuropathological findings are reported of a 6-month-old female child with a "cerebral" lactic acidosis. A mutation in the pyruvate dehydrogenase (PDH) E1 alpha gene was found. Gross examination of the brain revealed a severe thinning of the cerebral parenchym, a marked hydrocephalus sparing the aqueduct and fourth ventricle, agenesis of the corpus callosum and heterotopic noduli of gray matter in subependymal regions. Microscopical examination showed heterotopic inferior olives, absent pyramids and focal neuroglial overgrowth into meninges. In addition some heterotopia of purkinje cells and dysplasia of the dentate nuclei were observed. There was a marked vascular proliferation with many thin-walled, congestive vessels in the cerebral and cerebellar white matter, and to a lesser extent in the striatum. To our knowledge these cerebellar and vascular abnormalities have not been reported before in patients with "cerebral" lactic acidosis. The combination of these neuropathological findings might be characteristic for PDH deficiency and more specifically for its E1 alpha subtype. Neuropathological examination could lead to the retrospective diagnosis of PDH E1 alpha deficiency in those cases where biochemical investigations were not or incompletely performed. This may have potential implications for genetic counseling.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |
9/9. An autopsy case of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) with a point mutation of mitochondrial dna.A 14-year-old boy with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) is reported. He had suffered blepharoptosis and cataracts prior to the stroke-like episodes, and was thus reported in 1984 as having Kearns-Shy (Sayre) syndrome. After his death, an A-to-G mutation of the mitochondrial dna (mtDNA) at bp 3243 was identified in cardiac muscle and the liver. Neuropathologically, multiple old and recent necrotic foci were observed in the gray and white matter of the cerebrum and cerebellum. These lesions were occasionally observed in areas outside of the distribution of major blood vessels of the brain. In the recent necrotic foci, neural loss and sponginess were observed while some neurons were preserved intact. The latter finding has not been described in MELAS and suggests that metabolic degeneration had occurred in the neurons of this patient. This is the first report of a confirmed 3243 mutation of the mtDNA in an autopsied MELAS case.- - - - - - - - - - ranking = 0.16666666666667keywords = vessel (Clic here for more details about this article) |