Fig. 2.

Colitis with a diffuse colitis pattern in a 64-year-old man with advanced melanoma treated with ipilimumab, presenting with diarrhea.

Coronal reformatted contrast-enhanced CT image of the abdomen obtained at 2.6 months after the initiation of ipilimumab treatment demonstrated a new fluid-filled dilated colon (asterisk) with mucosal hyperemia indicating diffuse colitis. Colonoscopic biopsy confirmed colonic inflammation with mucosal injury consistent with ipilimumab-associated colitis. Patient was treated with oral steroids followed by intravenous infliximab, leading to resolution of the findings on the follow-up scan at 1.8 months after the onset (data not shown).