Table 3. TNF-α Blockade-Associated Colitis.

Agent	Colitis	Histology features	Clinical presentation	Treatment	Clinical outcome	References
Infliximab	UC (n = 1)	Chronic active colitis with cryptitis, crypt abscesses, architectural distortion, dense lymphoplasmacytic infiltrate	Bloody diarrhea 2 weeks after his fourth infliximab inclusion	Cessation of infliximab; Parental steroids; Mesalamine	Resolved	[6]
	Apoptotic enteropathy (n = 1)	Architectural distortion, empty appearing lamina propria, cystically dilated crypts with atrophic epithelial lining, scattered apoptosis of basal crypt epithelium	Watery diarrhea	Cessation of infliximab	Diarrhea improved at 1 month following the last dose of infliximab	[8]
	Ischemic colitis (n = 13)	N/A	N/A	N/A	3 died; 9 recovered; 1 without follow-up data	[9]
	Intestinal TB	Intestinal and pulmonary TB (n = 1)	N/A	N/A	N/A	[12]
		Intestinal, pulmonary, brain TB (n = 1)	Worsening diarrhea	Anti-TB treatment	Died 8 months after diagnosis of TB	[13]
	CMV colitis (n = 1)	Features not well depicted in the text; No pictures from H&E stained sections presented; Pictures from immunostain equivocal for CMV at the most	Developed abdominal discomfort, anorexia, epigastric pain, watery diarrhea at 10 days after the third dose of infliximab	Cessation of infliximab and starting ganciclovir	No recurrence of diarrhea at 30 months of follow-up	[15]
Adalimumab	Ischemic colitis (n = 13)	Ischemic colitis without vasculitis on right hemicolectomy specimen (n = 1)	Developed post-prandial bilious vomiting, right flank and upper quadrant cramping pain and diarrhea 1 week after initiating adalimumab for RA	Right hemicolectomy	Alive after right hemicolectomy	[16]
		N/A (n = 12)	N/A	N/A	1 died; 10 recovered; 1 without follow-up data	[9]
	Apoptotic enteropathy (n = 2)	Increase in apoptotic bodies in the duodenum and mild increase in apoptotic bodies in the colon	Diarrhea or abdominal pain	N/A	N/A	[17]
	Disseminated TB with mycobacteria detected in feces (n = 1)	N/A	N/A	N/A	N/A	[12]
	Indolent T-cell lymphoproliferative disease of the gastrointestinal tract (n = 1)	Active chronic colitis and multiple foci of small lymphocyte infiltrates expanding the lamina propria of the inflamed mucosa without crypt destruction. The T cells are CD8+, TIA-1+, TCRβ-F1+ with TCRG and TCRB gene rearrangement by PCR study	Not mentioned	Cessation of adalimumab	Monoclonal T-cell infiltrate reappeared at the only site of active inflammation	[18]
Certolizumab pegol	Ischemic colitis (n = 3)	N/A	N/A	N/A	1 recovered; 1 without follow-up data	[9]
Etanercept	UC	N/A	Developed diarrhea; No resolution of UC after cessation of etanercept, need anti-IBD standard therapy and/or other anti-TNF-α agent	N/A	N/A	[19]
		Histology of UC (n = 1)	Developed bloody diarrhea after 28 months on etanercept for JRA	Flaring on adalimumab and infliximab, resolution only after cessation of all anti-TNF agents	Healing UC confirmed by colonoscopy 10 months after cessation of infliximab	[6]
		Histology of UC (n = 3) and one with microgranuloma	N/A	Cessation of etanercept and need anti-IBD with anti-TNF-α agents in two patients	Resolution in 2; 1 without follow-up data	[27]
	CD (n = 9)	Epithelioid granuloma present; Also with upper gastrointestinal tract involvement	N/A	Cessation of etanercept in most cases, need anti-IBD standard therapy and/or other anti-TNF-α agent	4 with remission; 5 without remission	[26, 27]
	Ischemic colitis (n = 7)	N/A	N/A	N/A	1 died; 6 recovered	[9]
	Apoptotic enteropathy (n = 1)	Prominent apoptotic bodies in the duodenum and mild increase in apoptotic bodies in the colon	Diarrhea	N/A	N/A	[17]
	Sarcoid-like lesions	N/A	N/A	N/A	N/A	[28]

CD: Crohn’s disease; JRA: Juvenile rheumatoid arthritis; N/A: information not available; RA: rheumatoid arthritis; TB: tuberculosis; TNF: tumor necrosis factor; UC: ulcerative colitis.