Abstract:
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive multisystem disorder that often presents with gastrointestinal and neurological symptoms. Here we report a 33-year-old male who presented with a 16-year history of diarrhea with black stool and progressive weight loss. He complained of progressive bilateral blurred vision, upper eyelids heaviness, ocular motility impairment, and color blindness. Peripheral neuropathy, bilateral sensorineural deafness, hyperlactatemia, diabetes mellitus, hepatic steatosis, blood coagulation dysfunction, and diffuse leukoencephalopathy were detected in the systemic evaluation. Based on the novel homozygous pathogenic variant in the TYMP gene (c.1159+1G>A), he was diagnosed with MNGIE. On ophthalmic examinations, the thickness of the inner retina and ganglion cell complex significantly decreased. ERG showed diffusely decreased amplitudes. The electronegative electroretinogram, which was first reported in MNGIE, indicated a more severe inner retina impairment. The bilateral papillomacular bundle defect and central vision loss in MNGIE are consistent with classical mitochondrial optic neuropathies\' features. According to the literature, pigmentary retinopathy, optic neuropathy, and abnormal pupillary reflexes are uncommon ocular features of MNGIE. This study contributes to a better understanding of ocular manifestations in MNGIE and demonstrates that MNGIE may have dyschromatopsia and an electronegative electroretinogram.
摘要:
线粒体神经胃肠脑肌病(MNGIE)是一种罕见的常染色体隐性多系统疾病,通常表现为胃肠道和神经系统症状。在这里,我们报告了一名33岁的男性,他有16年的腹泻史,伴有黑色粪便和进行性体重减轻。他抱怨进行性双侧视力模糊,上眼睑沉重,眼运动性障碍,和色盲。周围神经病变,双侧感音神经性耳聋,高乳酸血症,糖尿病,肝脂肪变性,凝血功能障碍,在系统评估中检测到弥漫性白质脑病。基于TYMP基因中的新型纯合致病变异(c.1159+1G>A),他被诊断出患有MGIE。在眼科检查中,内视网膜和神经节细胞复合体的厚度明显下降。ERG显示振幅弥漫性降低。负电性视网膜电图,首先在MNGIE中报道,表明内部视网膜损伤更严重。MNGIE的双侧乳头状囊束缺损和中心视力丧失与经典的线粒体视神经病变特征一致。根据文献,色素性视网膜病变,视神经病变,瞳孔反射异常是MNGIE的罕见眼部特征。这项研究有助于更好地了解MNGIE中的眼部表现,并表明MNGIE可能具有色觉障碍和负电性视网膜电图。