Infections due to dysregulated immunity: an emerging complication of cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have revolutionised cancer treatment. However, immune-related adverse events (irAEs) are a common side effect which can mimic infection. Additionally, treatment of irAEs with corticosteroids and other immunosuppressant agents can lead to opportunistic infection, which we have classed as immunotherapy infections due to immunosuppression. However, emerging reports demonstrate that some infections can be precipitated by ICIs in the absence of immunosuppressive treatment, in contrast to the majority of reported cases. These infections are characterised by a dysregulated inflammatory immune response, and so we propose they are described as immunotherapy infections due to dysregulated immunity. This review summarises the rapidly emerging evidence of these phenomena and proposes a new framework for considering infection in the context of cancer immunotherapy.

Automated summary

Immune checkpoint inhibitors (ICIs) have greatly impacted cancer treatment, but immune-related adverse events (irAEs) and infections caused by immunosuppression are common issues. However, some infections can be triggered by ICIs without immunosuppressive treatment, characterized by dysregulated immune responses. A new framework is needed to consider such infections in the context of cancer immunotherapy.