{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T02:10:55Z","timestamp":1758161455348,"version":"3.44.0"},"reference-count":17,"publisher":"Mathematical Modelling and Numerical Simulation with Applications","issue":"01","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Pediatr Genet"],"published-print":{"date-parts":[[2023,3]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>\n          Introduction\u2003IQSEC2-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.<\/jats:p><jats:p>\n          Case Report\u2003We 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.<\/jats:p><jats:p>\n          Conclusion\u2003IQSEC2-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.<\/jats:p>","DOI":"10.1055\/s-0040-1721371","type":"journal-article","created":{"date-parts":[[2020,12,7]],"date-time":"2020-12-07T19:25:58Z","timestamp":1607369158000},"page":"076-080","source":"Crossref","is-referenced-by-count":0,"title":["Response to Steroids in IQSEC2-Related Encephalopathy Presenting with Rett-Like Phenotype and Infantile Spasms"],"prefix":"10.53391","volume":"12","author":[{"given":"Divya","family":"Nagabushana","sequence":"additional","affiliation":[{"name":"Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aparajita","family":"Chatterjee","sequence":"additional","affiliation":[{"name":"Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raghavendra","family":"Kenchaiah","sequence":"additional","affiliation":[{"name":"Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ajay","family":"Asranna","sequence":"additional","affiliation":[{"name":"Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gautham","family":"Arunachal","sequence":"additional","affiliation":[{"name":"Department of Human Genetics, National Institute of Mental Health and Neurosciences, Bengaluru, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ravindranadh Chowdary","family":"Mundlamuri","sequence":"additional","affiliation":[{"name":"Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"31409","published-online":{"date-parts":[[2020,12,7]]},"reference":[{"issue":"01","key":"ref1","first-page":"33","article-title":"Disruption of the IQSEC2 transcript in a female with X;autosome translocation t(X;20)(p11.2;q11.2) and a phenotype resembling X-linked infantile spasms (ISSX) syndrome","volume":"1","author":"M Morleo","year":"2008","journal-title":"Mol Med Rep"},{"issue":"06","key":"ref2","doi-asserted-by":"crossref","first-page":"486","DOI":"10.1038\/ng.588","article-title":"Mutations in the guanine nucleotide exchange factor gene IQSEC2 cause nonsyndromic intellectual disability","volume":"42","author":"C Shoubridge","year":"2010","journal-title":"Nat Genet"},{"issue":"04","key":"ref3","doi-asserted-by":"crossref","first-page":"496","DOI":"10.1111\/cge.13507","article-title":"Deep phenotyping of 14 new patients with IQSEC2 variants, including monozygotic twins of discordant 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Med"},{"issue":"09","key":"ref13","doi-asserted-by":"crossref","first-page":"2017","DOI":"10.1002\/ajmg.a.37132","article-title":"Mutations in epilepsy and intellectual disability genes in patients with features of Rett syndrome","volume":"167A","author":"H E Olson","year":"2015","journal-title":"Am J Med Genet A"},{"issue":"01","key":"ref14","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1002\/humu.23670","article-title":"IQSEC2 mutation update and review of the female-specific phenotype spectrum including intellectual disability and epilepsy","volume":"40","author":"C Shoubridge","year":"2019","journal-title":"Hum Mutat"},{"issue":"11","key":"ref15","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1016\/S1474-4422(05)70199-X","article-title":"The United Kingdom Infantile Spasms Study (UKISS) comparing hormone treatment with vigabatrin on developmental and epilepsy outcomes to age 14 months: a multicentre randomised trial","volume":"4","author":"A L Lux","year":"2005","journal-title":"Lancet Neurol"},{"issue":"08","key":"ref16","doi-asserted-by":"crossref","first-page":"948","DOI":"10.1177\/0883073809356107","article-title":"Outcomes in treatment of infantile spasms with pulse methylprednisolone","volume":"25","author":"J R Mytinger","year":"2010","journal-title":"J Child Neurol"},{"key":"ref17","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.pediatrneurol.2017.03.017","article-title":"Short-term outcome of intravenous methylprednisolone pulse therapy in patients with infantile spasms","volume":"71","author":"H R Yeh","year":"2017","journal-title":"Pediatr Neurol"}],"container-title":["Journal of Pediatric 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