MEFV and juvenile idiopathic arthritis: Several studies have shown an increased rate of MEFV mutations and FMF among patients with chronic inflammatory diseases other than IBD, particularly with certain types of vasculitis (IgA vasculitis and PAN-like vasculitis), systemic onset of juvenile idiopathic arthritis (JIA), and spondyloarthropathies (37–39, 41, 49–52).