J Pediatr Genet 2023; 12(01): 076-080
DOI: 10.1055/s-0040-1721371
Case Report

Response to Steroids in IQSEC2-Related Encephalopathy Presenting with Rett-Like Phenotype and Infantile Spasms

Divya Nagabushana
1   Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India
Aparajita Chatterjee
1   Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India
Raghavendra Kenchaiah
1   Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India
Ajay Asranna
1   Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India
Gautham Arunachal
2   Department of Human Genetics, National Institute of Mental Health and Neurosciences, Bengaluru, India
Ravindranadh Chowdary Mundlamuri
1   Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India
› Author Affiliations


Introduction IQSEC2-related encephalopathy is an X-linked childhood neurodevelopmental disorder with intellectual disability, epilepsy, and autism. This disorder is caused by a mutation in the IQSEC2 gene, the product of which plays an important role in the development of the central nervous system.

Case Report We describe the symptomatology, clinical course, and management of a 17-month-old male child with a novel IQSEC2 mutation. He presented with an atypical Rett syndrome phenotype with developmental delay, autistic features, midline stereotypies, microcephaly, hypotonia and epilepsy with multiple seizure types including late-onset infantile spasms. Spasms were followed by worsening of behavior and cognition, and regression of acquired milestones. Treatment with steroids led to control of spasms and improved attention, behavior and recovery of lost motor milestone. In the past 10 months following steroid therapy, child lags in development, remains autistic with no further seizure recurrence.

Conclusion IQSEC2-related encephalopathy may present with Rett atypical phenotypes and childhood spasms. In resource-limited settings, steroids may be considered for spasm remission in IQSEC2-related epileptic encephalopathy.


The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published, and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Publication History

Received: 29 August 2020

Accepted: 14 October 2020

Article published online:
07 December 2020

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