Coffin-Lowry syndrome (CLS) is a rare neurodevelopmental condition caused by heterogeneous mutations in the RPS6KA3 gene on the X chromosome, leading to severe intellectual disability and dysmorphism in men, while women are carriers and only weakly affected. CLS is well known for stimulus-induced drop episodes; however, epilepsy is not commonly reported in this condition. We report on a CLS patient presenting with recurrent episodes of nonconvulsive status epilepticus (NCSE) with generalized epileptic activity, for which investigations did not find any other cause than the patient's genetic condition. This case underlines that the possibility of nonconvulsive epileptic seizures and status epilepticus should, therefore, be considered in those patients. The treatable diagnosis of NCSE may easily be overlooked, as symptoms can be unspecific.

Keywords:
Coffin-Lowry syndrome, Nonconvulsive status epilepticus, RPS6KA3 mutation c.575G>C (p.R192T), Stimulus-induced drop episodes
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2015
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