An 11-year follow-up of neonatal onset bath-induced alternating hemiplegia of childhood in monozygotic twins

We previously reported on the initial manifestations in a set of female twins, who presented soon after birth bath-induced paroxysmal events each time they were immersed in (the warm water of) a bath. These episodes progressively ceased by the age of 36 months replaced by paroxysmal episodes of alternating hemiplegia unrelated to water immersion. By age 4 years the twins developed the classical features of alternating hemiplegia of childhood. Clinical outcomes at the age of 11 years are now reported. Standard and video-EEGs showed a large slow background activity followed by lower amplitude waves without focal abnormalities or other abnormal findings. This represents the first report on: (a) alternating hemiplegia of childhood started with bath-induced paroxysmal episodes; (b) this affection in monozygotic twin; (c) an 11-year follow up study in which the twins continue to experience episodes of alternating hemiplegia in the setting of baseline cognitive impairment without epileptic episodes.