MELAS is a mitochondrial respiratory chain disorder characterized by progressive neurodegeneration associated with stroke-like episode, increased plasma lactate levels and distinctive findings on neuroimaging studies. Hence we onset of right-sided hemiplegia accompanied by lactic acidosis and CT-Scan findings of diffuse hypodensity of the cerebral white matter at the time of the stroke-like episode. The diagnosis was confirmed by mutation analysis on blood and hair which showed the typical mtDNA A3243G mutation. This is the first local report of a confirmed case of MELAS.
Human ; Female ; Child Preschool ; MELAS SYNDROME ; MUSCULOSKELETAL DISEASES ; MUSCULAR DISEASES ; MITOCHONDRIAL MYOPATHIES ; MITOCHONDRIAL ENCEPHALOMYOPATHIES

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the classic mitochondrial diseases characterized by symptoms of repeated episodes of hemiparesis with mitochondrial DNA mutation. We report a rare case of early onset MELAS patient confirmed by genetic analysis with Wolff-Parkinson-White syndrome.
Acidosis, Lactic ; DNA, Mitochondrial ; Humans ; MELAS Syndrome ; Mitochondrial Diseases ; Mitochondrial Encephalomyopathies ; Mitochondrial Myopathies ; Paresis ; Wolff-Parkinson-White Syndrome

PURPOSE: The disease entity mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) is characterized by an early onset of stroke-like episodes. MELAS is the most dominant subtype of mitochondrial disease. Molecular genetic testing is important in the diagnosis of MELAS. The mitochondrial DNA (mtDNA) 3243A>G mutation is found in 80% of MELAS patients. Nevertheless, molecular analysis alone may be insufficient to diagnose MELAS because of mtDNA heteroplasmy. This study aimed to evaluate whether muscle biopsy is useful in MELAS patients as an initial diagnostic evaluation method. MATERIALS AND METHODS: The medical records of patients who were diagnosed with MELAS at the Department of Pediatrics of Gangnam Severance Hospital between January 2006 and January 2017 were reviewed. The study population included 12 patients. They were divided into two subgroups according to whether the results of muscle pathology were in accordance with mitochondrial diseases. Clinical variables, diagnostic evaluations, and clinical outcomes were compared between the two groups. RESULTS: Of the 12 patients, seven were muscle pathology-positive for mitochondrial disease. No statistically significant difference in clinical data was observed between the groups that were muscle pathology-positive and muscle pathology-negative for mtDNA 3243A>G mutation. Additionally, the patients with weakness as the initial symptom were all muscle pathology-positive. CONCLUSION: The usefulness of muscle biopsy appears to be limited to an initial confirmative diagnostic evaluation of MELAS. Muscle biopsy can provide some information in MELAS patients with weakness not confirmed by genetic testing.
Biopsy* ; Diagnosis ; DNA, Mitochondrial ; Genetic Testing ; Humans ; Medical Records ; MELAS Syndrome* ; Methods ; Mitochondrial Diseases ; Mitochondrial Encephalomyopathies* ; Molecular Biology ; Pathology ; Pediatrics

MELAS is the condition associated with mutant mtDNA that most closely mimics thrombotic cerebrovascular disease. It is characterized by mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes. These children develop short stature and either a focal or generalized seizure disorder. Ultimately, the patient presents with an acute hemiparesis that can alternate from side to side. In this article, we report the MELAS in siblings having point mutation in the mitochondrial DNA with an A to G transition at the 3,243rd position. MELAS is recognized as one of the several distinct syndromes containing cerebral infarct. And, mitochondrial DNA analyses, serum lactate level, and muscle biopsy are diagnostic clue of this syndrome.
Acidosis, Lactic ; Biopsy ; Child ; DNA, Mitochondrial ; Epilepsy, Generalized ; Humans ; Lactic Acid ; MELAS Syndrome* ; Mitochondrial Encephalomyopathies ; Paresis ; Point Mutation ; Siblings*

Mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome is a multisystem disorder, which is clinically characterized by encephalopathy, dementia, seizures and stroke-like episodes. Multiple organs can be affected and cardiac involvement often dominates the clinical picture because of its high energy requirement. We report a case of a 21-year-old woman with MELAS syndrome who had pre-excitation ECG and one episode of tachycardia attack.
Acidosis, Lactic ; Dementia ; Electrocardiography ; Female ; Humans ; MELAS Syndrome ; Mitochondrial Encephalomyopathies ; Seizures ; Tachycardia ; Wolff-Parkinson-White Syndrome ; Young Adult

Mitochondrial encephalomyopathy with lactic acid and stroke-like episodes (MELAS) is a multisystem mitochondrial disorder that typically presents in childhood. We report a case of MELAS syndrome diagnosed in a 45-year-old man presented with chronic kidney disease before a stroke-like episode. Genetic testing revealed a m.3243A>G point mutation in the mtDNA. The original diagnostic criteria for MELAS required the onset of stroke-like episodes prior to 40 years of age but this case demonstrates that disease onset may delay in certain individuals.
DNA, Mitochondrial ; Genetic Testing ; Humans ; Lactic Acid ; Late Onset Disorders ; MELAS Syndrome* ; Middle Aged ; Mitochondrial Diseases ; Mitochondrial Encephalomyopathies ; Point Mutation ; Renal Insufficiency, Chronic* ; Stroke

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes, abbreviated to MELAS, syndrome is a common mitochondrial disease that can present with a wide range of clinical symptoms, including seizures, stroke-like episodes, neuropathy, myopathy, sensorineural hearing loss, and encephalopathy. Although more than 90% of patients present with stroke-like episodes before the age of 40 years, some reports have described patients presenting later in life. Here, we report MELAS syndrome diagnosed in a 52-year-old Korean woman admitted because of altered mentality. She had a history of diabetes, sensorineural hearing loss, and cardiomyopathy. The patient's mentality fluctuated and her lactic acid level was elevated in the hospital. Although she was in her 50s, her medical history, encephalopathy, and lactic acidosis made us strongly suspect MELAS syndrome. The diagnosis was confirmed when a test showed the A3243G mitochondrial DNA mutation.
Acidosis, Lactic ; Cardiomyopathies ; Diabetes Mellitus ; DNA, Mitochondrial ; Female ; Hearing Loss, Sensorineural ; Humans ; Lactic Acid ; MELAS Syndrome ; Middle Aged ; Mitochondrial Diseases ; Mitochondrial Encephalomyopathies ; Muscular Diseases ; Seizures

PURPOSE: We evaluated brain perfusion SPECT findings of MELAS syndrome and mitochondrial myopathy in correlation with MR imaging in search of specific imaging features. MATERIALS AND METHODS: Subjects were five patients (four females and one male; age range, 1 to 25 year) who presented with repeated stroke-like episodes, seizures or developmental delay or asymptomatic but had elevated lactic acid in CSF and serum. Conventional non-contrast MR imaging and Tc-99m-ethyl cysteinate dimer (ECD) brain perfusion SPECT were performed and imaging features were analyzed. RESULTS: MRI demonstrated increased T2 signal intensities in the affected areas of gray and white matters mainly in the parietal (4/5) and occipital lobes (4/5) and in the basal ganglia (1/5), which were not restricted to a specific vascular territory. SPECT demonstrated decreased perfusion in the corresponding regions of MRI lesions. In addition, there were perfusion defects in parietal (1 patient), temporal (2), and frontal (1) lobes and basal ganglia (1) and thalami (2). In a patient with mitochondrial myopathy who had normal MRI, decreased perfusion was noted in left parietal area and bilateral thalami. CONCLUSION: Tc-99m ECD SPECT imaging in patients with MELAS syndrome and mitochondrial myopathy showed hypoperfusion of parieto-occipital cortex, basal ganglia, thalamus and temporal cortex, which were not restricted to a specific vascular territory. There were no specific imaging features on SPECT. The significance of abnormal perfusion on SPECT without corresponding MR abnormalities needs to be evaluated further in larger number of patients.
Basal Ganglia ; Brain* ; Female ; Humans ; Lactic Acid ; Magnetic Resonance Imaging ; Male ; MELAS Syndrome* ; Mitochondrial Encephalomyopathies ; Mitochondrial Myopathies* ; Occipital Lobe ; Perfusion ; Rabeprazole ; Seizures ; Thalamus ; Tomography, Emission-Computed, Single-Photon*

The importance of quality control for dramatically growing genetic tests continues to be emphasized with increasing clinical demands. Diagnostic genetics subcommitee of KSQACP performed two trials for cytogenetic study in 2002. Cytogenetic surveys were performed by 33 laboratories and answered correctly in most laboratories except some problems in nomenclature and analysis for mosaicism and cytogenetics of neoplasia. The molecular genetic test surveys include M. tuberculosis, HCV, HBV, leukemia/lymphoma, ABO genotyping, ApoE genotyping, spinocerebellar ataxia (SCA), spinal muscular atrophy (SMA), and mitochondrial encephalomyopathy, lactic acidosis, and stroke like episodes (MELAS). HBV, SCA, SMA, MELAS tests were the first challenge of the genetic survey. Molecular genetic survey showed excellent results in most participants, however, ABO genotyping tests should be improved by new methods in a few laboratories. External quality assessment program for diagnostic genetics could be helpful to give participants many chances of continuous education and of interesting case materials.
Acidosis, Lactic ; Apolipoproteins E ; Cytogenetics ; Education ; Genetics* ; Korea* ; MELAS Syndrome ; Mitochondrial Encephalomyopathies ; Molecular Biology ; Mosaicism ; Muscular Atrophy, Spinal ; Quality Control ; Spinocerebellar Ataxias ; Stroke ; Tuberculosis

MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) is one of the mitochondrial encephalomyopathy, A rare disease caused by a disturbance of the mitochondrial chain of respiration. MELAS is confirmed by typical light and electron microscopic findings : "ragged red fibers" by modified Gomori trichrome stain on light microscope and numerous abormal mitochondria on electron microscope. We experienced a boy with the characteristic clinical and pathologic findings of MELAS. Our patient demonstrated bilateral basal ganglia calcifications and infarction at right parieto-occipital and thalamic areas on CT and MR We found that MRI was more sensitive and represented the infarcted lesions better than CT. Detection of cerebral insults of MELAS by MRI is important in making decision on patient treatment and also in predicion of the patient prognosis.
Acidosis, Lactic ; Basal Ganglia ; Brain Diseases ; Child* ; Humans ; Infarction ; Magnetic Resonance Imaging ; Male ; MELAS Syndrome* ; Mitochondria ; Mitochondrial Encephalomyopathies ; Muscular Diseases ; Rare Diseases ; Respiration