目的 探讨 KCNQ2 基因变异相关吡哆醛反应性癫痫性脑病的临床特点和治疗。方法 回顾分析 2 例 KCNQ 2基因变异相关吡哆醛反应性癫痫性脑病患儿的临床资料，并复习相关文献。结果 例1，女性，于生后6天起病； 例 2，男性，于 7 月龄起病。2 例患儿均表现为难治性癫痫发作，同时伴精神运动发育落后。基因检测均证实有 KCNQ 2 基因变异，分别为c.2312C>T（p.Thr771Ile）和c.873G>C（p.Arg291Ser）。2例患儿均经钠离子通道阻滞剂及其他常规 抗癫痫药物治疗无效，加用大剂量维生素 B6后发作逐渐控制。结论 KCNQ 2 基因变异相关癫痫性脑病起病年龄早， 常合并智力、运动发育障碍 ；对钠离子通道阻滞剂治疗无效者可能存在吡哆醛依赖性，可尝试使用大剂量维生素 B6 治疗。

Objective To study the clinical features and treatment of pyridoxal-reponsive epilepsy encephalopathy caused by KCNQ 2 gene mutation. Methods The clinical data of two patients diagnosed with pyridoxal-responsive epilepsy encephalopathy caused by KCNQ 2 gene mutation were retrospectively analyzed, and related literature were reviewed. Results Case 1 is a female child with onset age of 6 days after birth, and case 2 is a male child with onset age of 7 months of age, both of them showed refractory seizures, accompanied by mental and motor developmental retardation. Treatment with sodium channel blockers and other anti-epileptic drugs is ineffective. The number of seizure attack gradually decreased after the add-on treatment of high-dose vitamin B6 . Pathogenetic variations of KCNQ 2 were confirmed by genetic testing: c. 2312 C>T; p.Thr 771 Ile and c.873G>C; p.Arg 291 Ser. Conclusion The age of onset of epilepsy caused by KCNQ 2 gene mutation is early, often combined with mental and motor retardation. In patients who have no effect on sodium channel blocker treatment may have pyridoxal dependence, which could try the high-dose of vitamin B6 treatment.