Modulation of cytokine production by intravenous immunoglobulin in patients with enterovirus 71-associated brainstem encephalitis

Background: Several epidemics of enterovirus 71 (EV71) infections occurred in Taiwan since 1998. Objectives: We performed the study to determine the changes in cytokine profiles associated with administration of intravenous immunoglobulin (IVIG) in patients with EV71-associated brainstem encephalitis complicated by autonomic nervous system (ANS) dysfunction and pulmonary edema. Study design: Plasma cytokine concentrations (IL-1β, IL-6, IL-8, IFN-γ, TNF-α, IL-2, IL-4, IL-5, IL-10, and IL-13) were monitored on admission and within 12-24 h after administration of IVIG in a cohort of children (n = 22) with virologically confirmed EV71 infection, from March 2000 through April 2004. Result: Plasma levels of IFN-γ, IL-6, IL-8, IL-10, and IL-13 levels significantly decreased in patients with pulmonary edema after administration of IVIG, P < 0.05. Plasma levels of IL-6 and IL-8 were significantly decreased in patients with ANS dysregulation after administration of IVIG, P < 0.05. Administration of IVIG was not associated with significant changes in plasma concentration of IL-1β, IL-2, IL-4, IL-5 IL-10, IL-13 and TNF-α in patients with ANS dysregulation. Conclusions: These findings suggest that IVIG might be considered to have a therapeutic role in EV71-associated brainstem encephalitis. A clinical trial is needed to support this hypothesis.