背景:MEF2C单倍功能不全综合征的特征是严重的智力残疾,癫痫,刻板的运动,轻微的畸形和大脑异常。我们报告了一个新的MEF2C突变患者的病例,将他的临床和影像学特征与文献中先前报道的特征进行比较。
方法:一名10岁男孩在11个月大的时候因严重的精神运动延迟而首次来到儿科神经科诊所,没有回归。他表现出广泛性张力减退,眼神接触不良,手口刻板印象,斜视和轻微的面部二态。癫痫发作始于26个月大,难治。脑MRI显示脑室周围白质信号略有增加,CSF空间整体扩大。分子分析显示,致病性和致病性MEF2C突变。
结论:MEF2C单倍体功能不全综合征最近被认为是一种神经发育障碍。严重的智力障碍,无法说话和癫痫是MEF2C突变患者的普遍特征,尽管据报道有重复的患者会出现轻度认知和言语障碍。部分缺失的患者可能没有癫痫。异常运动模式在MEF2C单倍功能不全患者中非常常见。延迟髓鞘形成似乎更常见于MEF2C突变患者。而仅在微缺失患者中报告了皮质发育的畸形。尽管MEF2C单倍体功能不全的患病率尚未确定,在具有严重智力障碍和Rett样特征的患者的鉴别诊断中应考虑它。
BACKGROUND: MEF2C haploinsufficiency syndrome is characterized by severe intellectual disability, epilepsy, stereotypic movements, minor dysmorphisms and brain abnormalities. We report the case of a patient with a new
MEF2C mutation, comparing his clinical and imaging features to those previously reported in the literature.
METHODS: A 10 year-old boy first came to pediatric neurology clinic at the age of 11 months because of severe psychomotor delay, without regression. He presented generalized hypotonia, poor eye contact, hand-mouth stereotypies, strabismus and minor facial dimorphisms. Epileptic seizures started at 26 months of age and were refractory. Brain MRI showed a slight increase in periventricular white matter signal and globally enlarged CSF spaces. Molecular analysis revealed a de novo, pathogenic and causative
MEF2C mutation.
CONCLUSIONS: MEF2C haploinsufficiency syndrome was recently recognized as a neurodevelopmental disorder. Severe intellectual disability with inability to speak and epilepsy are universal features in patients with MEF2C mutations, although mild cognitive and speech disorders have been reported to occur in patients with duplications. Epilepsy might be absent in patients with partial deletions. Abnormal movement patterns are very common in patients with
MEF2C haploinsufficiency. Delayed myelination seems to be more commonly observed in patients with MEF2C mutations, while malformations of cortical development were only reported in patients with microdeletions. Although
MEF2C haploinsufficiency prevalence is yet to be determined, it should be considered in the differential diagnosis of patients with severe intellectual disability and Rett-like features.