Long-term prognosis of patients with infantile spasms following ACTH therapy

The influence of ACTH on the prognosis of patients with infantile spasms remains controversial. We have examined retrospectively the long-term benefits of initially successful ACTH therapy in patients treated at this institution between 1961 and 1974. Individuals with equivocal or minimal improvement during ACTH therapy were excluded from this study. Eighteen affected infants showed a favorable early response consisting of cessation of seizures for at least 3 weeks during ACTH therapy and concurrent disappearance of the hypsarhythmic EEG pattern. Modal age at last follow-up was 5 years (range, 15 months to 16 years). Infantile spasms recurred in 7 patients (39%), and 8 patients subsequently had other seizure types. All epileptiform (spike) activity disappeared from the EEGs of 8 patients during ACTH therapy, but in 4 of these cases epileptiform activity was present in later tracings. In the remaining 10 patients the hypsarhythmic pattern disappeared in association with ACTH therapy, but the EEG remained epileptiform (often only in sleep). Later EEGs were free of epileptiform activity in 5 of the 10 patients whose tracings contained spike discharges in the early follow-up period. Four patients (22%) were seizure free and without intellectual impairment when last evaluated.