Immune Checkpoint Inhibitor Nephrotoxicity: Update 2020.

Area of Science:

• Nephrology
• Oncology
• Immunology

Background:

• Immune checkpoint inhibitors (ICPIs) have revolutionized cancer treatment but can cause autoimmune adverse events, notably acute kidney injury (AKI).
• ICPI-associated AKI (ICPI-AKI) is an increasingly recognized complication in cancer patients, presenting diagnostic and management challenges.
• Understanding ICPI-AKI is crucial for oncologists and nephrologists managing cancer patients receiving immunotherapy.

Purpose of the Study:

• To review the incidence, risk factors, and diagnostic challenges of ICPI-AKI.
• To propose a novel classification system for ICPI-AKI to address diagnostic uncertainty.
• To discuss clinicopathologic features, treatment strategies, and special considerations for ICPI-AKI.

Main Methods:

• Review of existing literature on ICPI-associated adverse events, focusing on AKI.
• Analysis of incidence, risk factors (e.g., PPI use, CKD, combination immunotherapy), and diagnostic criteria.
• Discussion of treatment modalities, including kidney biopsy and steroid therapy.
• Exploration of ICPI use in solid organ transplantation and rechallenge after ICPI-AKI.

Main Results:

• ICPI-AKI incidence and risk factors are detailed, highlighting challenges in prior definitions.
• A novel classification system (definite, probable, possible ICPI-AKI) is proposed to manage diagnostic uncertainty.
• Key clinicopathologic features and treatment strategies, including the role of kidney biopsy and steroids, are discussed.
• The complexities of ICPI use in transplant recipients and the implications of ICPI rechallenge are explored.

Conclusions:

• ICPI-AKI is a significant clinical issue requiring careful diagnosis and management.
• The proposed classification system aims to standardize the diagnosis of ICPI-AKI.
• Further research is needed, particularly regarding ICPI use in transplant patients and rechallenge strategies.