Department of Pediatric Neurology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey.
Department of Medical Genetics, Samsun Education and Research Hospital, Samsun, Turkey.
J Child Neurol. 2024 Jun;39(7-8):260-267. doi: 10.1177/08830738241263243. Epub 2024 Jul 25.
Hyperekplexia is a rare neurogenetic disorder that is classically characterized by an exaggerated startle response to sudden unexpected stimuli. This study aimed to determine clinical and genetic characteristics of our patients with hyperekplexia.
The age of onset and diagnosis, familial and perinatal history, clinical course, complications, metabolic screening tests, magnetic resonance imaging (MRI), medications, neuropsychometric evaluations, and gene mutations of patients diagnosed with hyperekplexia were reviewed retrospectively.
All hyperekplexia patients had displayed neonatal excessive startle response and muscle stiffness, which we accepted as the major form of the disorder. Sixteen patients had mutations in genes associated with hyperekplexia. The ages at clinical diagnosis and genetic confirmation ranged from newborn to 16 years old and from 2.5 to 19 years, respectively. Nine patients (56.25%) were initially misdiagnosed with epilepsy. Seven patients (43.75%) carried a diagnosis of intellectual disability, defined here as a total IQ <80. Delayed gross motor development was detected in 4 patients (25%), and speech delay was reported in 3 (18.75%). Mutations in (NM_000171.4) and (NM_004211.5) were identified in 13 (81.25%) and 3 patients (18.75%), respectively. Fifteen of the 16 patients (93.75%) showed autosomal recessive inheritance. Only 1 patient (6.25%) showed autosomal dominant inheritance.
Although hyperekplexia is a potentially treatable disease, it can be complicated by delayed speech and/or motor acquisition and also by intellectual disability. This study shows that hyperekplexia is not always a benign condition and that all patients diagnosed with hyperekplexia should be evaluated for neuropsychiatric status and provided with genetic testing.
发作性过度惊跳症是一种罕见的神经遗传性疾病，其特征为对突发的意外刺激出现明显的惊跳反应。本研究旨在确定发作性过度惊跳症患者的临床和遗传特征。
回顾性分析诊断为发作性过度惊跳症患者的发病年龄和诊断年龄、家族史和围产期病史、临床病程、并发症、代谢筛查试验、磁共振成像（MRI）、药物治疗、神经心理评估和基因突变。
所有发作性过度惊跳症患者均表现为新生儿过度惊跳反应和肌肉僵硬，我们将其作为该疾病的主要表现形式。16 例患者的基因发生了与发作性过度惊跳症相关的突变。临床诊断和基因确认的年龄范围分别为新生儿至 16 岁和 2.5 至 19 岁。9 例（56.25%）患者最初被误诊为癫痫。7 例（43.75%）患者被诊断为智力障碍，这里定义为总智商 <80。4 例（25%）患者存在粗大运动发育延迟，3 例（18.75%）患者存在语言发育迟缓。13 例（81.25%）和 3 例（18.75%）患者分别发现 （NM_000171.4）和 （NM_004211.5）基因突变。16 例患者中有 15 例（93.75%）表现为常染色体隐性遗传，仅有 1 例（6.25%）表现为常染色体显性遗传。
尽管发作性过度惊跳症是一种潜在可治疗的疾病，但它可能导致语言和/或运动发育迟缓以及智力障碍。本研究表明，发作性过度惊跳症并非总是良性疾病，所有诊断为发作性过度惊跳症的患者均应评估神经精神状态，并进行基因检测。
