细胞色素C氧化酶缺乏的可逆性线粒体肌病1例

A Case of Reversible Cytochrome C Oxidase Deficiency Myopathy

目的:了解细胞色素C氧化酶缺乏的可逆性线粒体肌病临床特征及基因突变特点。方法:回顾分析1例婴儿细胞色素C氧化酶缺乏的可逆性线粒体肌病的临床资料及基因检测结果。结果:本例患儿系婴儿起病,生长发育落后,入院时呼吸衰竭,需气管插管下呼吸机辅助呼吸,神经系统查体未见异常,动脉血气分析pH 7.212、血乳酸6.3 mmol/L、二氧化碳分压73.8 mm Hg、肌酸激酶1193 U/L、肌酸激酶同工酶155 U/L及乳酸脱氢酶560 U/L。头颅磁共振成像(MRI)示脑白质髓鞘化进程落后。入院后抗感染及辅助治疗效果不佳,持续高乳酸血症、肌酶水平异常升高。经辅酶Q_(10)、左卡尼丁治疗,临床症状明显改善。基因检测示线粒体基因组存在m.14674 T>C突变,来源于母亲。结论:婴幼儿持续呼吸衰竭、血乳酸水平高需警惕线粒体肌病,基因检测有助于及时诊断,细胞色素C氧化酶缺乏的可逆性线粒体肌病临床表现无特异性,早期诊治预后良好。

Objective:To investigate the clinical characteristics and gene mutation characteristics of reversible cytochrome C oxidase(COX)deficiency myopathy.Methods:The clinical data and gene testing results of infantile reversible COX deficiency myopathy in one case were retrospectively analyzed.Results:The child was an infant with onset of disease,backward growth and development,admitted into the hospital with respiratory failure and required ventilatory assistance under tracheal intubation.The neurological examination did not show any abnormality,and the arterial blood gas analysis showed pH 7.212,blood lactate 6.3 mmol/L,partial pressure of carbon dioxide 73.8 mm Hg,creatine kinase 1,193 U/L,creatine kinase isoenzyme 155 U/L and lactate dehydrogenase 560 U/L.Magnetic resonance imaging(MRI)of the head showed retardation with the process of myelination in alba.After admission,the anti-infective and adjuvant therapy was ineffective,with persistent hyperlactatemia and abnormally elevated myocardial enzyme level.The clinical symptoms of the child were significantly improved after treatment with coenzyme Q10 and levocanidine.Genetic testing showed m.14674 T>C mutation in the mitochondrial genome,derived from the mother.Conclusion:Persistent respiratory failure and high blood lactate in infants and children require vigilance for mitochondrial myopathy,and genetic testing can help to diagnose it in a timely manner.The clinical manifestations of reversible COX deficiency myopathy are nonspecific,and early diagnosis and treatment can lead to good prognosis.