Infants with ISs due to tuberous sclerosis or postinfectious injury exhibit exceptionally high CSF NGF concentrations, far exceeding values observed in age-matched controls or cryptogenic cases, whereas infants with ISs of structural or hypoxic origin often show reduced NGF levels and poorer responsiveness to ACTH therapy [160,161,162,163,164,202,203]. Here, NGF is linked to tuberous sclerosis.