[Effect of carbamazepine on epilepsy with 1p36 deletion syndrome]

The 1p36 deletion syndrome is caused by submicroscopic deletion in the subtelomeric region of chromosome 1. Epilepsy is one of the most important features of the syndrome, in addition to the characteristic facial appearance, cardiac anomaly, dysphagia, deafness, mental retardation and growth delay. We identified three patients with this syndrome and assessed the features of complicated epilepsy. In all cases, epilepsy developed during infancy. The seizure types were mainly focal seizure and multiple seizure types including tonic seizure and tonic-clonic seizure. Interictal electroencephalogram showed focal abnormalities. Noticeably, two developed epileptic spasms and hypsarrhythmia in electroencephalogram, just after the administration of carbamazepine (CBZ). Including cases showing epileptic spasms, their epilepsy was easily tractable with anti-epileptic drugs, which could be withdrawn as they aged. All had deleted potassium channel beta subunit (KCNAB2) and gamma-aminobutyric acid A receptor delta (GABRD). CBZ may aggravate various epileptic syndromes, especially, those caused by GABA-A receptor gene mutation. Our cases may suggest the novel correspondence of GABA-A receptor-related epilepsy syndrome and exacerbation of epilepsy triggered by CBZ.