Although the pathophysiology and thus TNF disposition of children with JIA and adults with RA might be similar, as evidenced by similar TNF levels in synovial fluid [39, 40] it is unknown whether the TNF disposition in the eye of children with NIU is comparable to the concentrations in the synovial fluid of children with JIA and intestinal tissue in IBD. This evidence concerns the gene TNF and rheumatoid arthritis.