Infantile Spasms and Developmental Delay: A Case of Miller–Dieker Syndrome

Abstract

Background: Miller–Dieker syndrome (MDS) is a rare genetic disorder, due to contiguous gene deletion on chromosome 17p13.3, characterized by classical type I lissencephaly, severe developmental delay, seizures, cardiac defects, and dysmorphisms. West syndrome is a severe form of epilepsy with epileptic spasms, hypsarrhythmia in electroencephalogram (EEG), and neuropsychomotor delay. Herein, we describe the neurophysiological and neuroimaging findings of a patient with MDS with associated West syndrome. Clinical Description: A 5-month-old boy was brought with new-onset infantile spasms and a history of delay and some regression in milestones. Facial dysmorphism was noted in the form of a prominent forehead, bitemporal hollowing, short nose with upturned nares, thickened upper lip, long philtrum, low-set ears, and hypertelorism. There was hypotonia of all four limbs. Management and Outcome: An EEG showed hypsarrhythmia, and the magnetic resonance imaging brain revealed hypoplastic sulci with pachygyria and smooth cortical surface of supratentorial brain parenchyma – features suggestive of lissencephaly type 1. Echocardiography showed atrial septal defect and minimal pericardial effusion. Whole-exome sequencing showed a contiguous large heterozygous deletion on chromosome 17 which was suggestive of Miller–Dieker lissencephaly syndrome. Parents were counseled, and the spasms were treated with an injection adrenocorticotropic hormone and oral vigabatrin. Conclusion: Structural brain abnormalities are well-known causes of infantile spasms. MDS is a severe malformative condition, lissencephaly being the hallmark of this disorder. This case report will create awareness among pediatricians regarding this rare condition with a characteristic combination of clinical features, which can be confirmed by brain imaging and genetic analysis.