Table 1.

Disease characteristics and differences among different immune‐mediated intestinal diseases

Type	Common site of involvement	Age of occurrence	Systemic features	Endoscopic features	Radiological features	Histological features	Laboratory findings	Treatment
Coeliac disease	Duodenum and jejunum	Any age	Growth failure, bone abnormalities, Dermatitis herpetiformis, Neurological symptoms, Vitamin deficiencies	Scalloping of duodenal folds, Mosaic pattern, Decreased fold height and number	Bowel wall thickening with stricture formation can be seen in ulcerative jejunitis or when complicated by lymphoma	Villous atrophy with increased intra epithelial lymphocytes	IgA tTG IgA EMA Anti‐DGP	Avoidance of gluten in diet
Gastrointestinal vasculitis	BD: Ileocolonic HSP: Duodenum and ileum SVV: both small and large bowel	BD: Second to third decade HSP: 3–15 years SVV: Fifth decade	Oro‐genital ulcers Sinusitis Respiratory symptoms, Glomerulonephritis, Palpable purpura	Oval punched‐out ulcers, erythema, edema	Bowel wall thickening with the target sign and engorgement of mesenteric vessels with comb sign	Acute/chronic inflammation Necrosis of the vessels Necrotizing granulomas	Elevated CRP, creatinine; Urinary active sediments ANCA HLA B51	Corticosteroids Cyclophosphamide Thiopurines Rituximab Mepolizumab Anti‐TNF
Eosinophilic gastroenteritis	Stomach and duodenum	Third to fifth decade	Asthma, Atopy	Edema, erythema, ulcerations, polypoidal lesions	Bowel wall thickening with or without ascites	Eosinophilic infiltration with ≥30 eosinophils/hpf	Eosinophilia >500 cells/mm3	Elimination diets Prednisolone Budesonide Cromolyn Montelukast Omalizumab Mepolizumab Lirentelimab
Microscopic colitis	Colon	Fifth to sixth decade	Autoimmune thyroiditis Type 1 DM Arthritis	Normal	None	CC: Collagen band ≥10 micrometers in diameter LC: ≥20 intraepithelial lymphocytes per 100 surface epithelial cells		Budesonide Cholestyramine Bismuth subsalicylate Thiopurines Anti TNF therapy Surgery
Immune checkpoint‐induced enterocolitis	Colon	‐	‐	Loss of vascular pattern, Friability, Ulcerations	Thickening with enhancement of bowel			Corticosteroids Anti‐TNF Vedolizumab
Monogenic variants of IBD	Colonic or ileocolonic	First decade	Skin manifestations Recurrent infections	Colitis, small bowel strictures and ulcerations	Thickening with enhancement of bowel, Perianal fistula	Lymphocytic infiltrates, Non‐necrotizing granulomas similar to CD	Immunoglobulin deficiency Low FOXP3 cells Abnormal neutrophil function tests	Anti TNF Abatacept Anti‐IL‐1 HSCT
Gastrointestinal sarcoidosis	Stomach Esophagus Colon	Second to fifth decade	Respiratory symptoms Skin manifestations Ocular manifestations	Diffuse gastric infiltration Pyloric stenosis Gastric polyps Ulceration	Bowel wall thickening Abdominal lymphadenopathy	Non‐caseating epithelioid granulomas	Elevated ACE, vitamin D 1,25 level Hypercalcemia, and hypercalciuria	Glucocorticoids

ACE, angiotensin converting enzyme; ANCA, antineutrophil cytoplasmic antibody; Anti‐DGP, anti deamidated gliadin peptide antibody; Anti IL1, anti interleukin‐1 antibody; Anti‐TNF, anti‐tumor necrosis factor antibody; BD, Behcet's disease; CC, collagenous colitis; CD, Crohn's disease; CRP, C‐reactive protein; FOXP3, Forkhead box P3; HLA, human leukocyte antigen; HSCT, hematopoietic stem cell transplantation; HSP, Henoch‐Schönlein purpura; IBD, inflammatory bowel disease; IgA EMA, anti endomysial antibody; IgA tTG, tissue transgutaminase antibody; LC, lymphocytic colitis; SVV, small vessel vasculitis.