Rai, NilshanThapa, MonikaPokharel, MerinaAcharya, JineeYadav, Dhirendra2025-10-302025-10-302022https://hdl.handle.net/20.500.14572/2918Authors Nilshan Rai KIST Medical College and Teaching Hospital, Gwarko, Lalitpur, Nepal Monika Thapa Department of Neurology, National Neuro Center, Maharajgunj, Kathmandu, Nepal Merina Pokharel Department of Neurology, National Neuro Center, Maharajgunj, Kathmandu, Nepal Jinee Acharya KIST Medical College and Teaching Hospital, Gwarko, Lalitpur, Nepal. Dhirendra Yadav Patan Academy of Health Sciences, Lagankhel, Lalitpur, NepalAbstract Down syndrome is a genetic disorder caused by an extra copy of chromosome number 21. New onset of seizure in adults with Down syndrome is rare. The exact pathogenesis of intracranial calcification and seizure in Down syndrome is unknown, however, a possible association between hypocalcemia and vitamin D deficiency in Down syndrome was reported. An 18-year-old girl with nasal bridge, mongoloid slants, clinodactyly and saddle gap of toes, and prominent Downs phenotypes was present with a low level of parathyroid hormone, calcium, and vitamin D. Due to a higher prevalence of intracranial calcification in people with Down syndrome, there is an increased possibility of hypocalcemia and vitamin D deficiency. Hence, serum levels of calcium and vitamin D should always be checked before starting treatment with anti-epileptic drugs.en-USBasal gangliaDown syndromeSeizureTrisomy 21Other