Corticosteroids in pediatric multiple sclerosis relapses

Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS) characterized by inflammatory attacks on oligodendroglia and axons. Clinical attacks can manifest as periods of acute muscle weakness or paralysis, sensory disturbances, and visual impairment. In adults, acute attacks with moderate physical impairment are commonly treated with corticosteroids [1], which have been found to decrease relapse duration [2] and shorten recovery time [3,4]. Corticosteroids are commonly used to treat acute attacks in children, although no clinical trials have been performed to evaluate their efficacy in this age group. This chapter will briefly review the use of corticosteroids for acute relapses in pediatric MS. Corticosteroids are widely used to treat inflammatory conditions as they modulate the immune system through multiple mechanisms. Many of their effects are exerted by altering gene transcription via interaction with the glucocorticoid receptor (GCR). T cells are present in MS lesions and are felt to participate in the inflammatory reaction [5]. Activated T cells are differentiated into either a Th1 or Th2 population based upon the types of cytokines that are produced. Th1 cells secrete the pro-inflammatory cytokines IL-12, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ. Activated Th2 cells have been found to modulate inflammation via production of IL-10 and transforming growth factor (TGF)-β. Corticosteroids reduce production of Th1 cytokines [6] while increasing the secretion of anti-inflammatory Th2 cytokines [7]. They also decrease immunoglobulin secretion and opsonization [8–10].