The Uncommon Yet Fatal Colitis

Abstract

Ipilimumab is a monoclonal antibody that improves survival in patients with metastatic melanoma. Ipilimumab causes T-cell activation, leading to increased immune response, and subsequent immune regulated effects such as diarrhea, colitis, bowel ischemia, and bowel perforation. Per Burdine et al, ipilimumab-induced colitis occurs in 30% of patients with roughly 10% of these patients requiring surgery. A 64 year old female with metastatic melanoma was started on ipilimumab. Approximately 3 months later, she developed diarrhea and PET CT imaging showed diffuse colonic uptake with mild pericolonic stranding. Stool culture and C. difficile PCR were negative. The patient underwent a colonoscopy revealing 10 cms of severe linear and deep ulceration in the sigmoid colon with biopsy findings significant for acute colitis with ulceration that was negative for dysplasia, granuloma, or cytomegalovirus. Given the severity of diarrhea and presence of colonic ulceration, the patient was started on a prednisone taper. Two months later, the patient developed diarrhea, fever, and abdominal pain requiring hospital admission. An abdominal obstruction series revealed air within the abdomen. She underwent a subtotal colectomy with end ileostomy for findings of ischemic colitis with micro-perforation of the transverse colon and perforation at the splenic flexure. Her post-operative course was significant for a focus on improving nutritional status. The patient had follow-up with oncology after discharge, and she decided to pursue hospice given her overall prognosis. Ipilimumab is a monoclonal antibody used for the treatment of metastatic melanoma and associated with immune regulated effects such as diarrhea, colitis, and ischemia/bowel perforation. Steroid therapy is the standard treatment for ipilimumab-induced colitis, but infliximab can be considered for refractory cases. It was not subsequently utilized in this case given the rapid progression of her disease to bowel perforation. This case demonstrates that with worsening diarrhea and abdominal discomfort, surgery may be warranted as the potential for colonic inflammation and bowel perforation associated with ipilimumab use, can mimic that of severe Crohn's disease.Figure: Ulceration of the sigmoid colon.Figure: Large amount of free air within the abdomen.