Table 1.

Colitis Grade Based Table.

Diarrhea or Colitis Grade (CTCAE version 5.0)	Laboratory testing*	Imaging	Endoscopy	Initial Treatment	Management of first line treatment failure
1	TTG-IgA, IgA HepB sAg, sAb, cAb Testing for latent tuberculosis infection Consider: stool cultures, C. difficile testing, and ova and parasite testing; fecal elastase; calprotectin or lactoferrin	Routine cross-sectional imaging is not recommended except where extraluminal complications such a perforation or abscess are of clinical concern	Consider only for patients with atypical presentations, including very early onset symptoms, or after discontinuation of immunotherapy	Empiric treatment with motility slowing agents such as loperamide oratropine-diphenoxylate	Manage as grade 2
2	TTG-IgA, IgA HepB sAg, sAb, cAb Testing for latent tuberculosis infection stool cultures, C. difficile testing Consider: ova and parasite testing; fecal elastase; calprotectin or lactoferrin	As grade 1	Consider flexible sigmoidoscopy prior to initiation of systemic corticosteroids; upper endoscopy or colonoscopy may be appropriate in patients with normal flexible sigmoidoscopies	Empiric treatment with motility slowing agents such as loperamide oratropine-diphenoxylate may be appropriate for patients where diarrhea is the only system Empiric systemic corticosteroids may be considered (0.5–1 mg/kg prednisone or equivalent daily followed by a 4–6 week taper) For patients with biopsy confirmed disease, systemic corticosteroid treatment is advised; patients with colonic ulceration should be considered for high-dose systemic corticosteroids (1–2 mg/kg prednisone or equivalent daily) and early induction of biologic therapy (either infliximab or vedolizumab)	Endoscopio biopsy confirmation of the diagnosis prior to escalation of therapy Consider fecal elastase and detection of CMV in the endoscopio biopsy either by cell culture or IHC. Add biological therapy (infliximab or vedolizumab],
3	As for grade 2	As for grade 1	Flexible sigmoidoscopy or colonoscopy should be strongly considered prior to initiation of systemic corticosteroids; upper endoscopy may be appropriate in patients with normal lower endoscopies	Empiric systemic corticosteroids may be considered (0.5–1 mg/kg prednisone or equivalent daily followed by a 4–6 week taper) with oral or intravenous For patients with biopsy confirmed disease, systemic corticosteroid treatment is advised either oral or intravenous; patients with colonic ulceration should be considered for high-dose systemic corticosteroids (1–2 mg/kg prednisone or equivalent daily) starting with intravenous therapy, as well as early induction of biologic therapy (either infliximab or vedolizumab)	Endoscopio biopsy confirmation of the diagnosis prior to escalation of therapy Consider fecal elastase and detection of CMV in the endoscopio biopsy either by cell culture or IHC. Add biological therapy (infliximab or vedolizumab]
4	As for grade 2	As for grade 1	As for grade 3	Consider hospitalization, otherwise as for grade 3	As for grade 3

Abbreviations: TTG-IgA (tissue transglutaminase-immunoglobulin A), IgA (immunoglobulin A), HepB (Hepatitis B Virus), sAg (surface antigen), sAb (surface antibody), cAb (core antibody), IHC (immunohistochemistry)

^*Routine monitoring of comprehensive metabolic panels, complete blood counts, and TSH are recommended for all patients undergoing immunotherapy