Juvenile idiopathic arthritis

Abstract

The term juvenile idiopathic arthritis (JIA) describes a heterogeneous group of several disease subtypes characterized by arthritis beginning before the age of 16 years and where symptoms persist for more than 6 weeks. All subtypes of JIA are of unknown cause. Although the pathogenesis for each subtype is likely to be different, JIA is generally regarded to be an autoimmune disease with the possible exception of systemic JIA. The∈causes are probably a combination of environmental (e.g., infectious) factors and immunogenetic (e.g., specific human leukocyte antigen [HLA] alleles) susceptibility. As there is no pathognomonic test for these disorders, the diagnosis is based upon the combined evaluation of the history, clinical presentation, and, to some extent, laboratory investigations. © Springer-Verlag London Limited 2010.