Table 4. Anti-CD20 (Rituximab)-Associated Colitis.

Case	Age (years)	Gender	Underlying disease	Rituximab dose and duration	Other treatment	Interval between completion to symptoms of colitis	Diagnosis	Histology confirmation	Follow-up	Reference
1	62	Female	Marginal zone B cell lymphoma	Several cycles of RTX (2002 - 2005) and four doses in 2005	None	Not mention (short)	Diffuse colitis with pneumatosis	Fulminant colitis on subcolectomy specimen	Symptom recurred 5 years later after receiving a second course of four cycles of RTX, developed biopsy proven colitis.	[63]
2	67	Male	Relapse of follicular lymphoma	Four cycles of fludarabine, cyclophosphamide with rituximab and then maintenance therapy with RTX at a dose of 375 mg/m2 every 3 months for a total of six cycles	None	2 months after his sixth cycle of RTX	Diffuse pancolitis	Confirmed by histology on subtotal colectomy	Patient died of recurrence of bacterial pneumonia 4 months after surgery.	[68]
3	26	Female	Non-Hodgkin lymphoma	N/A	N/A	N/A	Fulminant colitis	Confirmed by histology on colectomy	N/A	[69]
4	45	Female	Grave’s disease (clinical trial)	After the second infusion with weekly dose of 375 mg/m2	None	During treatment	Ulcerative colitis	Confirmed by sigmoidoscopy and biopsy	Mesalamine induced remission on day 650.	[67]
5	4	Male	Refractory nephrotic syndrome	4-week course of rituximab at a dose of 375 mg/m2	FK-506	6 weeks after RTX therapy	Severe ulcerative colitis	Confirmed by colonoscopy and biopsy	Corticosteroid induced remission with endoscopic and histologic healing.	[66]
6	34	Unknown	Bullous SLE	After three infusions at a dose of 375 mg/m2	N/A	During treatment	Ulcerative colitis	Confirmed by colonoscopy and biopsy	Episode of acute appendicitis with appendectomy. Later developed UC. Symptoms resolved upon RTX discontinuation.	[70]
7	38	Female	Refractory seronegative rheumatoid arthritis	N/A	None	13 weeks	Ulcerative colitis	Confirmed by colonoscopy and biopsy	Corticosteroid and 5-ASA induced remission; follow-up biopsy one year after RTX cessation showed restoration of B cells in the colonic mucosa and resolution of colitis.	[64]
8	80	Female	Small lymphocytic lymphoma	RTX 3-month maintenance	R-CVP	3 months	Crohn’s disease	Confirmed by colonoscopy/biopsy and resection histology	Surgical resection	[62]
9	74	Male	Grade 2 follicular lymphoma	RTX 3-month maintenance	R-CHOP	22 months	Crohn’s disease	Confirmed by colonoscopy and biopsy inflammation and small granulomata	Treated with hydrocortisone	[62]

N/A: information not available; R-CHOP: rituximab, cyclophosphamide, hydroxydaunomycin, vincristine, prednisolone; R-CVP: rituximab, cyclophosphamide, vincristine, and prednisolone; RTX: rituximab; SLE: systemic lupus erythematosus.