Pathophysiology of massive infantile spasms: perspective on the putative role of the brain adrenal axis.

Massive infantile spasms are an age-specific seizure syndrome of infancy. Uniquely, the spasms respond to hormonal manipulation using adrenocorticotropic hormone (ACTH) or glucocorticoids. A hypothesis explaining the efficacy of hormonal therapy, age-specificity, multiple causative factors, and spontaneous resolution of infantile spasms is presented. Corticotropin-releasing hormone (CRH), an excitant neuropeptide suppressed by ACTH/steroids, is implicated. Evidence for the age-specific convulsant properties of CRH is presented, and a putative scenario in which a stress-induced enhancement of endogenous CRH-mediated seizures is discussed. Clinical testing of the CRH-excess theory and its therapeutic implications are suggested.