Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018681 (headache)
 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied 40 MELAS patients (21 male and 19 female) to characterize the clinical features and biochemical and muscle biopsy findings related to the mtDNA mutation at the nucleotide position of 3,243, the most common genetic defect in MELAS. The most frequent symptom was episodic sudden headache with vomiting and convulsions, which commonly affected patients aged 5 to 15 years (80%). Biochemical defects in the muscle were variable; 13 patients had complex I, seven complex IV, and four complexes I + IV deficiencies. In four muscle biopsies without ragged-red fibers or any enzyme defect, we based the diagnosis on the identification of strongly SDH-reactive blood vessels, which occurred in 87.5% of the biopsies. The mtDNA mutation was present in 32 of 40 patients (80%). We conclude that there are no clinical and pathologic differences between the patients with and without this mtDNA mutation.
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PMID:Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS): a correlative study of the clinical features and mitochondrial DNA mutation. 154 15

A female patient who had clinical characteristics of MELAS but with no apparent muscle symptoms was reported. She was in good health until 12 years and 5 months of age when she began to have afebrile generalized tonic-clonic convulsions. Thereafter, she had repeated stroke-like episodes, including headache, vomiting, convulsions, hemiparesis and left ehemianopsia. She had neither muscle weakness, fatigability nor atrophy. Laboratory examinations disclosed elevated lactate and pyruvate levels in the serum and cerebrospinal fluids, transient focal low density areas on brain CT and right sensorineural deafness by audiometry. No ragged-red fibers (RRF) were found in the first biopsy at 13 years and 6 months of age, and two RRF-like fibers containing red granular materials in the subsarcolemnal regions in the second at 15 years and 3 months of age. A biochemical assay on the two biopsied muscles demonstrated normal enzyme activities in the mitochondrial electron transport system. She was diagnosed as having MELAS because of remarkable mitochondrial abnormalities in smooth muscle cells in the intramuscular arterioles which were clearly demonstrated by succinic dehydrogenase (SDH) stain and on electron microscopy. It was suggested that the stroke-like episodes in this patient were induced by a preferential damage to the mitochondria in the blood vessel walls. Thus, we conclude that a simple method of identifying the strongly SDH-reactive blood vessels (SSV) in frozen sections is critical in supporting or making diagnosis of MELAS.
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PMID:[MELAS without ragged-red fibers: a case report]. 176 Feb 9

We report a 9 year-old boy with MELAS. High dosed oral thiamine administration and high fat diet induced remarkable neurological and biochemical improvement. His mother had episodic headaches and hemiplegia, probably MELAS. He complained muscle weakness and repeated episodes of vomiting started from 2 years of age. High levels of serum lactate and pyruvate were recognized, but with no metabolic acidosis. He developed generalized muscle weakness, growth retardation, generalized convulsions and stroke-like episodes at 5 years old. Optic nerve atrophy and mental retardation gradually appeared. A muscle biopsy at 5 years old revealed numerous ragged-red fibers with excess accumulation of lipid droplets and glycogen particles. Scattered fibers had no cytochrome c oxidase (CCO) activity representing focal CCO deficiency. An electron microscopy showed markedly increased number of giant mitochondria filled with markedly proliferated complicated cristae. Pyruvate dehydrogenase complex level in the fibroblasts was within normal ranges. Serum carnitine level was normal. With oral administration of thiamine hydrochloride (1000 mg) and high fat diet (60-70%), muscle weakness improved, and lactate and pyruvate levels in the serum reduced to normal ranges, whereas the mental deterioration, muscle atrophy, pes cavus progressed very slowly. He died from cardiac and renal failures at 9 years old. Autopsied muscles showed a marked decrease in cytochrome c oxidase activity (biochemically 12.8% of the normal level), and almost all muscle fibers had no cytochrome c oxidase activity histochemically. The progression of the MELAS was probably in parallel with the decrease in CCO activity.
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PMID:[A case of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) with progressive cytochrome c oxidase deficiency]. 255 13

A 12-year-old boy with corticosteroid-responsive mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) is described. His mother proved to have an asymptomatic mitochondrial myopathy on examination of a muscle biopsy specimen. Three weeks after the onset of vomiting, headache, ataxia and visual and speech impairment, he presented with a background of somatic growth retardation, deafness and school failure. Examination revealed disorientation, dysphasia, dyspraxia, optic atrophy, hemianopia, hemiparesis and sensory inattention. A cranial computed tomographic scan disclosed a large, low-density area, which was consistent with infarction, in the left posterior hemisphere and marked calcification of the basal ganglia bilaterally. Within two weeks of the commencement of corticosteroid treatment, the neurological dysfunction resolved. Attempts to decrease the dosage of dexamethasone caused an exacerbation of symptoms repeatedly. Two weeks after ceasing corticosteroid therapy, the patient developed a serious neurological relapse and a new, large, low-density area, which resembled an infarction, in the right posterior hemisphere on a computed tomographic scan. The reintroduction of corticosteroid therapy again resulted in the rapid resolution of all symptoms. It became evident that the patient had an exquisitely sensitive corticosteroid dependency, whereby a reduction in the dexamethasone dosage of even 0.25 mg a day caused confusion, headaches and increasing lactic acidaemia. Although it is difficult to assess the impact of various therapies in MELAS because of the episodic natural course of the disease, this remarkable corticosteroid responsiveness also has been noted in four previously reported patients with MELAS syndrome; therefore, it would seem reasonable to suggest that corticosteroid therapy now should be considered as standard treatment for this condition. However, corticosteroid therapy in other forms of mitochondrial disorders still awaits careful evaluation.
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PMID:Mitochondrial encephalomyopathy with corticosteroid dependence. 273 98

The case of 12 years-old boy with seizures, headache, severe vomit and focal neurological signs is reported. These episodes had several recurrences and regression with little neurologic deficits. In the investigation it was found: lactic acidosis; stroke like episodes and calcification in the basal ganglia on computerized axial tomography; ragged red fibers on muscle biopsy and decreased of cytochrome C oxidase in the muscle tissue. A revision about mitochondrial disorders with involvement of the central nervous system and muscle is made, with emphasis on diagnosis and recognition of MELAS.
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PMID:[MELAS (mitochondrial encephalopathy, lactic acidosis and stroke-like episodes): report of a case]. 283 Aug 68

Mitochondrial myopathy, encephalopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome is one of the mitochondrial encephalomyopathies that has distinct clinical features including stroke-like episodes with migraine-like headache, nausea, vomiting, encephalopathy and lactic acidosis. We report a 27-year-old woman who presented with partial seizure, stroke-like episodes including hemiparesis, hemianopia and hemihypethesia, sensorineural hearing loss, migraine-like headache, and lactic acidosis. Brain computed tomographic scan showed encephalomalacia in the right parieto-occipital area and recent hypodensity in the left temporoparieto-occipital area with cortical atrophy. Muscle biopsy revealed ragged-red fibers and paracrystaline inclusions in the mitochondria. Genetic study revealed an A to G point mutation at nucleotide position (np) 3243 of mitochondrial DNA. External ophthalmoplegia and ptosis were also found during two exaggerated episodes in this patient. Therefore, the overlapping syndrome of chronic progressive external ophthalmoplegia in the MELAS syndrome is considered in this case. Furthermore, we also found carnitine deficiency in this patient and she was responsive well to steroid therapy. Muscle biopsy also revealed excessive lipid droplets deposits. Therefore, the carnitine deficiency may occur in MELAS syndrome with the A to G point mutation at np 3243. We recommend the steroid or carnitine supplement therapy be applied to the MELAS syndrome with carnitine deficiency.
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PMID:CPEO and carnitine deficiency overlapping in MELAS syndrome. 748 81

A 4-year-old boy presented with developmental delay, aggressive behavior, and incoordination. His EEG showed a diffuse encephalopathy. At age 10 he developed convulsions and severe migraine-like headaches. Muscle wasting, arreflexia, and lactic acidemia following exercise were noted. Electromyography was myopathic and nerve conduction studies revealed a peripheral neuropathy. Muscle biopsy demonstrated variation in fiber size and an excess of lipid droplets. He than had several stroke-like episodes and periods of unconsciousness, associated with severe metabolic acidosis. Muscle cytochrome C oxidase was abnormally low. This boy displayed the classical clinical and biochemical features of MELAS syndrome, namely Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes. Treatment included carnitine, vitamin C, vitamin K, riboflavin, coenzyme Q10, and corticosteroids. He died at the age of 14 years following an episode of seizures, coma, and gastrointestinal hemorrhage. This is the first reported case of MELAS syndrome in Israel.
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PMID:MELAS syndrome: peripheral neuropathy and cytochrome C-oxidase deficiency: a case report and review of the literature. 772 60

The clinical manifestations and mitochondrial DNA (mtDNA) mutations in a Taiwanese family with a female proband exhibiting mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes syndrome are reported. Clinically, the proband had a stroke-like episode with right hemiparesis, hemianopsia and mental dysfunction as well as short stature, hearing impairments, and elevated lactate levels. Brain magnetic resonance images showed multiple increased signal intensities over the left frontal, parietal and temporal areas. There were no ragged-red fibers, but paracrystalline inclusion bodies were shown in the muscle biopsies under electron microscopic examination. A deficiency of NADH-CoQ reductase was also found in biochemical studies of the muscles. The family survey revealed no abnormal findings except for headache and episodic vomiting in her mother. The molecular analysis of mtDNA disclosed a mutation from A to G at the nucleotide pair 3243 of the mitochondrial transfer RNA(Leu) gene in the blood, hair follicles and/or muscle of the maternal relatives. A characteristic finding of the MELAS family is variation of percentage of mutated mtDNA in various tissues and individuals. However, a higher proportion of mutated mtDNA was noted in the proband than that in the asymptomatic or oligosymptomatic family members. From the data, the variable clinical phenotypes in this MELAS family can be explained at least partly, by the different proportions of mutant mtDNA in the target tissues of the proband and maternal relatives.
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PMID:MELAS syndrome: correlation between clinical features and molecular genetic analysis. 788 36

The clinical manifestations of mitochondrial encephalomyopathy are described in four generations of a single kindred. The age of onset of major neurological disturbance varied from 3-70 years. In some patients, deafness was the only manifestation; in others, recurrent bouts of status epilepticus associated with focal neurological deficits and headache, caused severe disability or death. Examples of all three adult forms of mitochondrial encephalomyopathy: MELAS, MERFF and Kearns Sayre syndrome, were represented within the kindred. Associated features included deafness, short stature, non-insulin-dependent diabetes mellitus, migraine, peptic ulceration and severe constipation. The nt 3243 A-G MELAS mutation was detected in two members of the kindred. This study highlights the diversity of clinical expression of a mitochondrial mutation within a single kindred.
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PMID:Mitochondrial encephalomyopathy: variable clinical expression within a single kindred. 835 Jan 9

We describe a 42-year-old woman with overlapping syndrome of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) and MERRF (myoclonus epilepsy and ragged-red fibers). Clinically, she had episodic headache, stroke-like episode with left hemiparesis and lactic acidosis commonly found in MELAS syndrome. However, myoclonus seizure, and ataxia with dyssynergic gait characteristic of MERRF were also noted. Computed tomographic scans showed a right temporo-parietal hypodense lesion. The lesion disappeared 20 months later, even magnetic resonance images also failed to reveal this abnormality. A molecular analysis of mitochondrial DNA was conducted by using restriction endonucleases ApaI and NaeI. A transition from A to G was found at the nucleotide position 3243, but not found at the 8344th nucleotide pair. In this report, we document the fluctuating CT changes and emphasize the importance of molecular analysis in patients with overlapping syndrome of mitochondrial encephalomyopathies.
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PMID:Overlapping syndrome of MERRF and MELAS: molecular and neuroradiological studies. 835 81


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