Khurana D S, Salganicoff L, Melvin J J, Hobdell E F, Valencia I, Hardison H H, Marks H G, Grover W D, Legido A
1Section of Neurology, St Christopher's Hospital for Children, Department of Pediatrics, Drexel University College of Medicine, Philadelphia 19134, USA.
Neuropediatrics. 2008 Feb;39(1):8-13. doi: 10.1055/s-2008-1076737.
The purpose of this study was to determine the relationship between epilepsy and respiratory chain defects in children with mitochondrial encephalopathies (ME).
We conducted a retrospective review of the medical records of children referred for evaluation of an ME. Only patients assigned a definite diagnosis of ME using modified Walker criteria and with a respiratory chain defect were included. Clinical data pertaining to the ME and epilepsy type were collected. Mitochondria were isolated by subcellular fractionation from a vastus lateralis muscle biopsy and studies were performed using polarographic and spectroscopic techniques for the quantitative determination of NADH and cytochrome components of the respiratory chain.
A total of 38 children with ME were identified. Seizures were present in 61%. Sixteen of 23 children with epilepsy (70%) had refractory epilepsy associated with a progressive encephalopathy. Children with epilepsy had a significantly higher incidence of complex I defects than children without epilepsy (p<0.01). Complex III and IV defects were significantly higher in patients without epilepsy (p<0.01 and p<0.05, respectively) than in those with epilepsy.
Epilepsy is an important component of ME. The higher incidence of complex I defects in patients with epilepsy suggests a possible relationship between mitochondrial oxidative stress dysfunction and epileptogenic process.
本研究旨在确定线粒体脑肌病（ME）患儿癫痫与呼吸链缺陷之间的关系。
我们对因ME评估而转诊的儿童病历进行了回顾性研究。仅纳入使用改良沃克标准确诊为ME且存在呼吸链缺陷的患者。收集了与ME和癫痫类型相关的临床数据。通过亚细胞分级分离法从外侧股肌活检中分离出线粒体，并使用极谱法和光谱技术对呼吸链的NADH和细胞色素成分进行定量测定。
共确定了38例ME患儿。61%的患儿出现癫痫发作。23例癫痫患儿中有16例（70%）患有与进行性脑病相关的难治性癫痫。癫痫患儿中复合体I缺陷的发生率显著高于无癫痫患儿（p<0.01）。无癫痫患者中复合体III和IV缺陷显著高于癫痫患者（分别为p<0.01和p<0.05）。
癫痫是ME的重要组成部分。癫痫患者中复合体I缺陷的发生率较高，提示线粒体氧化应激功能障碍与致痫过程之间可能存在关联。
