• Journal of Genetic Medicine
• /
• v.1 no.1
• /
• pp.39-43
• /
• 1997

The mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is inherited maternally, in which the MTTL1*MELAS 3243 mutation has been most commonly found as a heteroplasmy of A to G point mutation in the $tRNA^{Leu(UUR)}$ gene. The MTTL1*MELAS 3271 mutation is known to be the second common mutation, though clinical features of both mutations are not remarkably different. Recently, a variety of minor mutations have been reported in patients with MELAS. In this study, major efforts have been made to investigate the allele frequency of major three mutations including MTTL1*MELAS 3243, 3252, 3271 in 10 Korean families with MELAS probands. The PCR and subsequent direct sequencing of the PCR product in the regions spanning these three mutation sites were employed to identify the mutation in each proband. All family members have been screened for the presence of these three mutations by PCR-RFLP assay using Apa I, Acc I and Bfr I restriction enzymes. The MTTL1*MELAS 3243 mutation was most commonly found (7 out of 10 families tested) followed by the MTTL1*MELAS 3271 which was identified in 1 out of 10 families. In the remaining 2 families none of three mutations were found, indicating the presence of either nuclear mutation or yet unidentified mitochondrial DNA mutation in these families.

• The Journal of Pediatrics of Korean Medicine
• /
• v.13 no.2
• /
• pp.225-235
• /
• 1999

MELAS is the condition associated with mutant mtDNA that most closely mimics thrombotic cerebrovascular disease. Characteristic abnormalities are two. first, 'ragged-red fibers' in muscle biopsy. second, point mutation in the mitochondrial DNA analyses. The characteristic clinical presentations of MELAS are short stature, recurrent stroke like episodes, migraine-like headache, sensorineural hearng loss, glucose intolerance and neuropathy. We now report a case of MELAS syndrome having mitochondrial DNA mutation with an A to G transition at the 3,243rd position diagnosed in Chung-ang Hospital.

• Annals of Clinical Neurophysiology
• /
• v.8 no.1
• /
• pp.84-87
• /
• 2006

The MELAS (Mitochondrial Encephalomyopathy with Lactic Acidosis, and Stroke-like episodes) syndrome is one of the inherited mitochondrial disorder. We have experienced a 16-year-old girl with headaches and left hemianopsia. Diagnosis of MELAS syndrome with multiple brain parenchymal lesions was confirmed by gene study. The stroke-like lesion of MELAS syndrome showed significant improvement in radiological follow up study. Therefore, MRI findings in MELAS could be interpreted as metabolic cellular dysfunction rather than ischemic vasculopathy.

• Herbal Formula Science
• /
• v.18 no.2
• /
• pp.267-277
• /
• 2010

Objective : Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke like episodes (MELAS) syndrome is a progressive neurodegenerative disorder. The typical presentation of patients with MELAS syndrome includes features such as mitochondrial encephalomyopathy, lactic acidosis, and stroke like episodes. Other features, such as seizures, diabetes mellitus, hearing loss, cardiac disease, short stature, endocrinopathies, exercise intolerance, and neuropsychiatric dysfunction are clearly part of the disorder. Approximately 80% of patients with the clinical characteristics of MELAS syndrome have a genetic mutation. This progressive disorder is reported to have a high morbidity and mortality. This case report is intended to estimate clinical effects of oriental meedicinal treatment of MELAS syndrome. Methods : A 44 year old female patient diagnosed as MELSA syndrome was treated with general oriental medicinal therapy including acupuncture, moxibustion, cupping, pharmacupunture and herbal medication in 20XX in Wonkwang Medical Center Gwangju. And the changes in symptoms and signs were evaluated as time dependently. Results : Although there is currently no curable treatment and MEALS syndrome is tend to progress, our treatment showed improvement in general weakness, gait disturbance and pain in the patient. Conclusion : Our case report suggests that various oriental medicinal treatment could be effective for improvement of MELAS syndrome and may represent a new potential therapeutic approach to control the disease. It could be applied to improve general condition, prevent relapse, enhance the quality of life and reduce complaints in the patient.

• Annals of Clinical Neurophysiology
• /
• v.24 no.2
• /
• pp.84-89
• /
• 2022

Vestibular dysfunction has rarely been reported in MELAS syndrome. A 40-year-old male with long-term diabetes and hearing loss experienced a stroke-like episode with hemisensory disturbance and lactic acidosis. Brain MRI showed temporo-parieto-occipital cortical lesions, and a final diagnosis was made of MELAS syndrome with the mitochondrial 3243A>G mutation. Neuro-otologic evaluations revealed anterior-canal-sparing bilateral impairments of the vestibulo-ocular reflex in the video head impulse test and no caloric paresis. This unique pattern of vestibular dysfunction may aid in diagnosing MELAS syndrome.

• Journal of Life Science
• /
• v.14 no.2
• /
• pp.296-300
• /
• 2004

We investigated feasibility of using the formalin-fixed and paraffin-embedded tissue to study mitochondrial mutations in the case that fresh or frozen tissue, or blood samples are not available. Four paraffin blocks of muscle biopsies in Korean MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) patients were chosen. Total DNA was extracted from these blocks for PCR/RFLP analysis, and sequencing was performed to study the most common mutation, A to G transition at nucleotide position 3243 underlying MELAS in the mitochondrial tRN $A^{Leu(UUR)}$ gene. We could identify the A to G mutation at nt.3243 in three MELAS patients. Our results show that the mitochondrial genome of our paraffin blocks is presumably in good condition. Our results are in accordance with the previous findings by other investigators that PCR allows molecular genetic analysis of paraffin-embedded tissues stored in most histopathology laboratories.s.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.23 no.1
• /
• pp.17-24
• /
• 2023

Purpose: In the past, detection of metabolic abnormalities in plasma amino acid (PAA) and urine organic acid (UOA) has been widely used to diagnose clinical mitochondrial diseases, such as mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). In this study, the diagnostic values of PAA and UOA were reviewed, and their effectiveness in the diagnosis of MELAS was examined retrospectively. Methods: Blood and urine samples at the time of diagnosis were collected from all clinically diagnosed MELAS patients (n=31), and PAA and UOA tests were performed. All samples were collected in a fasting state to minimize artifacts in the results. The difference in the ratio of abnormal metabolites of PAA and UOA at initial diagnosis was statistically compared between the MELAS with genetic confirmation (n=19, m.3243A>G mutation) and MELAS without genetic confirmation (n=12) groups. The MELAS without genetic confirmation group was used as control. Results: Comparison of PAA and UOA between the two groups revealed that no abnormal metabolites showed characteristic differences between gene-confirmed MELAS patients with and those without genetic confirmation. Conclusions: Abnormal values of metabolites in PAA or UOA might be useful as a screening test but are not sufficient to diagnose MELAS patients.

• Journal of Genetic Medicine
• /
• v.16 no.1
• /
• pp.31-38
• /
• 2019

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a maternally inherited mitochondrial disorder of which m.3243A>G is the most commonly associated mutation, resulting in an inability to meet the energy requirements of various organs. MELAS poses a diagnostic challenge owing to its multiple organ involvement and great clinical variability due to its heteroplasmic nature. We report three cases from a family who were initially misdiagnosed with myasthenia gravis or undiagnosed. Although there is no optimal consensus treatment approach for patients with MELAS because of the disease's heterogeneity, our 21-year-long therapy regimen of ${\text\tiny{L}}-arginine$, ${\text\tiny{L}}-carnitine$, and coenzyme Q10 supplementation combined with dietary management appeared to provide noticeable protection from the symptoms and complications. Prompt early diagnosis is important, as optimal multidisciplinary management and early intervention may improve outcomes.

• Investigative Magnetic Resonance Imaging
• /
• v.22 no.2
• /
• pp.119-122
• /
• 2018

Neurogenic weakness, ataxia and retinitis pigmentosa (NARP) syndrome is a rare maternally inherited mitochondrial disorder. Radiologic findings in NARP syndrome are varied; they include cerebral and cerebellar atrophy, basal ganglia abnormalities, and on rare occasions, leukoencephalopathy. This article describes an extremely rare case of NARP syndrome mimicking mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS).

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.16 no.2
• /
• pp.102-108
• /
• 2016

Mitochondrial encephalopathy, lactic acidosis, and stroke-like episode (MELAS) syndrome is one of mitochondrial encephalopathy. As the early clinical manifestations can be variable, it is important to suspect the disease, especially in patients with multiple organ dysfunctions. A boy was diagnosed with epilepsy when he was 9 years old. Two years later, severe headache and blurred vision developed suddenly. On examination, left homonymous hemianopsia was detected with corresponding cerebral parenchymal lesions in right temporo-occipito-parietal areas. MELAS syndrome was confirmed by genetic test, which showed m.3243 A>G mitochondrial DNA mutation. Multivitamins including coenzyme Q10 were added to anticonvulsant. He experienced 4 more events of stroke-like episodes over 5 years, but he is able to perform normal daily activities. A 13-year-old boy was brought to the hospital due to suddenly developed respiratory arrest and asystole associated with pneumonia. Past medical history revealed that he had multiple medical problems such as epilepsy, failure-to-thrive, optic atrophy, and deafness. He has been on valproic acid as an anticonvulsant which was prescribed from local clinic. He recovered after the resuscitation, but his cognition and motor function were severely damaged. He became bed-ridden. He was diagnosed with MELAS syndrome by brain MRI, muscle biopsy, and clinical features. Genetic test did not reveal any mitochondrial gene mutation. Four years later, he expired due to suddenly developed severe metabolic acidosis combined with hyperglycemic hyperosmolar nonketotic coma. The clinical features of MELAS syndrome are variable. Early diagnosis before the presentation to the grave clinical course may be important for the better clinical outcome.