Epilepsy and movement disorders in CDG: Report on the oldest‐known MOGS‐CDG patient

Congenital glycosylation disorders (CDG) are inherited metabolic diseases due to defective glycoprotein and glycolipid glycan assembly and attachment. MOGS‐CDG is a rare disorder with seven patients from five families reported worldwide. We report on a 19‐year‐old girl with MOGS‐CDG. At birth she presented facial dysmorphism, marked hypotonia, and drug‐resistant tonic seizures. In the following months, her motility was strongly limited by dystonia, with forced posture of the head and of both hands. She showed a peculiar hyperkinetic movement disorder with a rhythmic and repetitive pattern repeatedly documented on EEG‐polygraphy recordings. Brain MRI showed progressive cortical and subcortical atrophy. Epileptic spasms appeared in first months and ceased by the age of 7 years, while tonic seizures were still present at last assessment (19 years). We report the oldest‐known MOGS‐CDG patient and broaden the neurological phenotype of this CDG.

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