PDF(Pubmed)
Abstract：
UNASSIGNED: Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes (MELAS) syndrome is a rare mitochondrial disorder caused by mutations in mitochondrial DNA, resulting in impaired energy production and affecting multiple organs. We present a suspected MELAS syndrome case with the initial symptom of chest tightness.
UNASSIGNED: A 46-year-old man sought medical attention due to progressively worsening chest tightness during physical activity. He had been receiving treatment for type 2 diabetes for 15 years. One year ago, he presented with symptoms of hearing impairment. Transthoracic echocardiography revealed increased thickness of the left ventricular wall. Serum protein electrophoresis showed no evidence of light-chain amyloidosis, and the 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid scan showed no definite uptake in the heart muscle. The patient\'s head magnetic resonance imaging (MRI) indicated lacunar infarcts. The lactate threshold test was positive. The biopsy of the skeletal muscle showed broken red fibre infiltration on modified Gomori trichrome staining, and electron microscopy revealed signs of mitochondrial cardiomyopathy, including mild mitochondrial swelling, lipid accumulation, and myofibril damage. A whole-exome genetic test was used to detect the m.3243A>G mutation in the MT-TL1 gene. Based on these findings, MELAS syndrome was the most probable diagnosis.
UNASSIGNED: The patient presented with chest tightness in adulthood, without any accompanying psychoneurological symptoms. However, the patient presented with other symptoms, including diabetes mellitus, hearing loss, abnormal lactate levels, ischaemic lesions on head MRI, and left ventricular hypertrophy. By identifying a mutation in the MT-TL1 gene and conducting a muscle biopsy, the diagnosis of MELAS syndrome was definitively confirmed.
UNASSIGNED: A 46-year-old man sought medical attention due to progressively worsening chest tightness during physical activity. He had been receiving treatment for type 2 diabetes for 15 years. One year ago, he presented with symptoms of hearing impairment. Transthoracic echocardiography revealed increased thickness of the left ventricular wall. Serum protein electrophoresis showed no evidence of light-chain amyloidosis, and the 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid scan showed no definite uptake in the heart muscle. The patient\'s head magnetic resonance imaging (MRI) indicated lacunar infarcts. The lactate threshold test was positive. The biopsy of the skeletal muscle showed broken red fibre infiltration on modified Gomori trichrome staining, and electron microscopy revealed signs of mitochondrial cardiomyopathy, including mild mitochondrial swelling, lipid accumulation, and myofibril damage. A whole-exome genetic test was used to detect the m.3243A>G mutation in the MT-TL1 gene. Based on these findings, MELAS syndrome was the most probable diagnosis.
UNASSIGNED: The patient presented with chest tightness in adulthood, without any accompanying psychoneurological symptoms. However, the patient presented with other symptoms, including diabetes mellitus, hearing loss, abnormal lactate levels, ischaemic lesions on head MRI, and left ventricular hypertrophy. By identifying a mutation in the MT-TL1 gene and conducting a muscle biopsy, the diagnosis of MELAS syndrome was definitively confirmed.
摘要：
■线粒体脑肌病，乳酸酸中毒,和中风样发作（MELAS）综合征是一种罕见的线粒体疾病引起的线粒体DNA突变，导致能量产生受损并影响多个器官。我们提出了一个可疑的MELAS综合征病例，其最初症状为胸闷。
■一名46岁的男子因身体活动期间胸闷逐渐恶化而求医。他已经接受2型糖尿病治疗15年。一年前,他出现了听力障碍的症状。经胸超声心动图显示左心室壁厚度增加。血清蛋白电泳显示没有轻链淀粉样变性的证据，99mTc-3,3-二膦酰基-1,2-丙二羧酸扫描显示心肌没有明确的摄取。患者头部磁共振成像（MRI）提示腔隙性梗死。乳酸阈值试验为阳性。在改良的Gomori三色染色上，骨骼肌活检显示破碎的红色纤维浸润，电子显微镜显示线粒体心肌病的迹象，包括轻度线粒体肿胀,脂质积累，和肌原纤维损伤。采用全外显子组遗传试验检测MT-TL1基因中的m.3243A>G突变。基于这些发现,MELAS综合征是最可能的诊断。
■患者成年后出现胸闷，没有任何伴随的精神神经症状.然而,患者出现其他症状，包括糖尿病,听力损失,乳酸水平异常,头部MRI上的缺血性病变，左心室肥厚.通过识别MT-TL1基因的突变并进行肌肉活检，MELAS综合征的诊断得到明确确认.
■一名46岁的男子因身体活动期间胸闷逐渐恶化而求医。他已经接受2型糖尿病治疗15年。一年前,他出现了听力障碍的症状。经胸超声心动图显示左心室壁厚度增加。血清蛋白电泳显示没有轻链淀粉样变性的证据，99mTc-3,3-二膦酰基-1,2-丙二羧酸扫描显示心肌没有明确的摄取。患者头部磁共振成像（MRI）提示腔隙性梗死。乳酸阈值试验为阳性。在改良的Gomori三色染色上，骨骼肌活检显示破碎的红色纤维浸润，电子显微镜显示线粒体心肌病的迹象，包括轻度线粒体肿胀,脂质积累，和肌原纤维损伤。采用全外显子组遗传试验检测MT-TL1基因中的m.3243A>G突变。基于这些发现,MELAS综合征是最可能的诊断。
■患者成年后出现胸闷，没有任何伴随的精神神经症状.然而,患者出现其他症状，包括糖尿病,听力损失,乳酸水平异常,头部MRI上的缺血性病变，左心室肥厚.通过识别MT-TL1基因的突变并进行肌肉活检，MELAS综合征的诊断得到明确确认.
