Behçet disease (BD) and BD‐like clinical phenotypes: NF‐κB pathway in mucosal ulcerating diseases.

Behçet's disease (BD) is a heterogeneous multi‐organ disorder in search of a unified pathophysiological theory and classification. The disease frequently has overlapping features resembling other disease clusters, such as vasculitides, spondyloarthritides and thrombophilias with similar genetic risk variants, namely HLA‐B*51, ERAP1, IL‐10, IL‐23R. Many of the BD manifestations, such as unprovoked recurrent episodes of inflammation and increased expression of IL‐1, IL‐6 and TNFα, overlap with those of the hereditary monogenic autoinflammatory syndromes, positioning BD at the crossroads between autoimmune and autoinflammatory syndromes. BD‐like disease associates with various inborn errors of immunity, including familial Mediterranean fever, conditions related to dysregulated NF‐κB activation (eg TNFAIP3, NFKB1, OTULIN, RELA, IKBKG) and either constitutional trisomy 8 or acquired trisomy 8 in myelodysplastic syndromes. We review here the recent advances in the immunopathology of BD, BD‐like diseases and the NF‐κB pathway suggesting new elements in the elusive BD etiopathogenesis. [ABSTRACT FROM AUTHOR]