Spontaneous remission of infantile spasms and hypsarrhythmia following acute infection with high-grade fever.

To elucidate the pathogenesis of spontaneous remission of infantile spasms (ISs) and hypsarrhythmia following infection, we reviewed 58 patients with ISs from 1986 through 2006 in our hospital. Five patients showed spontaneous remission of spasms or hypsarrhythmia following infections with high-grade fever (SR group). In control, we analyzed five patients with complete improvement of ISs for ACTH therapy (ACTH group). In the SR group, ISs stopped in an average of 4.0 days after the onset of infection. In three patients performing EEG during the infection, hypsarrhythmia disappeared within an average of 8 days after the onset of infection. In the ACTH group, ISs stopped an average of 4.6 days and hypsarrhythmia disappeared within an average of 10 days after ACTH therapy. During the remission course of ISs, low-voltage background activity (BGA) on EEG showed in one patient of the SR group and in all patients of the ACTH group. ACTH is known to the efficacy for ISs and suppression of cortical activity on human EEG. This similar remission course between in the SR group and in the ACTH group suggest neuroendocrinal products in response to infection, which is resembled ACTH-related cascade, may play a role for spontaneous remission following infection.