ALK and hypersensitivity vasculitis: CD - Crohn's disease; IBD - inflammatory bowel disease; UC - ulcerative colitis; SES-CD - simplified endoscopic activity score for Crohn's disease; IUS - intestinal ultrasound; BWT - bowel wall thickness; TNF - tumor necrosis factor; SC - subcutaneously; ALK - anaplastic lymphoma kinase; LV - leukocytoclastic vasculitis; UST - ultrasound therapy; RCT - randomized controlled trial