Response to magnesium sulfate and adrenocorticotropic hormone combination therapy for infantile spasms with failed first-line treatments.

Importance: Infantile spasm (IS) is a kind of refractory epilepsy. The first-line treatments for IS are adrenocorticotropic hormone (ACTH), oral corticosteroids, and vigabatrin.

Objective: This study aimed to evaluate the efficacy of magnesium sulfate and ACTH (MgSO₄+ACTH) combination therapy in patients with IS who failed first-line treatments.

Methods: In this retrospective study, the clinical data of patients with IS who failed first-line treatments were collected in the Chinese PLA General Hospital. Patients received MgSO₄+ACTH combination therapy after first-line treatments failed. The course of treatments was 2 weeks. The therapeutic dose of ACTH and MgSO₄ was 2.5 U·kg^-1·d^-1 and 0.25 g·kg^-1·d^-1, respectively.

Results: A total of 229 patients with IS who failed the first-line treatments were collected. At the end of the MgSO₄+ACTH combination treatment, the seizure-free rate was 48.5% (111/229), and the resolution of hypsarrhythmia on electroencephalogram (EEG) was 72.1% (165/229). About 21.4% (49/229) of patients showed side effects, including infectious diseases, hypokalemia, and diarrhea.

Interpretation: For patients with IS who failed first-line treatments, in terms of the seizure-free rate and resolution of hypsarrhythmia on EEG, MgSO₄+ACTH combination therapy can be considered.