Acute liver failure in young children with systemic-onset juvenile idiopathic arthritis without macrophage activation syndrome: report of two cases.

Acute liver failure (ALF) with macrophage activation syndrome (MAS) is well known as a complication of systemic-onset juvenile idiopathic arthritis (S-JIA). However, liver failure without overt MAS is rare in S-JIA. We encountered two Japanese children with S-JIA in whom ALF developed during the remission of clinical manifestations. ALF without MAS was improved with plasma exchange and cyclosporine A combined with pulse methylprednisolone.