Immune checkpoint inhibitor-induced colitis complicated with inflammatory intestinal obstruction: a case report and literature review

Background: The combination therapy using anti-angiogenic drugs and immune checkpoint inhibitors (ICIs) has an excellent safety profile and manageable toxicity. However, ICI therapy may lead to a variety of autoimmune events, known as immune-related adverse events (irAEs), which some secondary complications may occur, such as immune-mediated colitis (IMC) and secondary inflammatory intestinal obstruction. It could impact clinical assessments and treatment decisions. Although there are few reports about secondary inflammatory intestinal obstruction related IMC. Case Description: We report an adult patient who suffered from primary liver cancer, who accepted ICIs (sintilimab) combined with vascular endothelial growth factor (VEGF) inhibitor (bevacizumab). He suffered worsening diarrhea about 5 days following immunotherapy. Computed tomography (CT) revealed the thickening intestinal wall of colon and rectum and massive cerebral gas in the proximal colon cavity. He was hospitalized with a diagnosis of IMC and inflammatory intestinal obstruction. Finally, he underwent the therapeutic option using combined glucocorticoid and somatostatin. His symptoms eased within 3 weeks and he was discharged from the hospital. Conclusions: IMC with diarrhea as the main manifestation requires early diagnosis and timely treatment. If the condition progresses, inflammatory intestinal obstruction may occur and this is a life-threatening situation. It is effective to accept early glucocorticoid and somatostatin while casual surgery may aggravate intestinal inflammation and injury, even death.