Immune checkpoint inhibitor-related acute kidney injury: A diagnostic and therapeutic challenge for nephrologists

Immune checkpoint inhibitor (ICI)-related acute kidney injury (AKI) is a rare but serious complication in cancer patients. The presenting features are often non-specific, making it difficult to distinguish from other, more commonly encountered pre-renal and post-renal causes. However, a precise diagnosis is imperative to instigate a proper management plan and minimise the inappropriate use of immunosuppression, which might have serious consequences for such sick patients. The indications for ICI use have increased over the years, and they will likely become the standard of care for many more difficult-to-treat malignancies in the future. Nephrologists will become increasingly involved in the management of such patients, especially in challenging decisions regarding withholding and restarting the treatment and starting immunosuppression. The current guidelines are ambiguous regarding the diagnostic workup and differ in their recommendations about the utility of a kidney biopsy, withholding the offending agent, and rechallenging with ICIs once AKI has resolved. This article tends to explore these questions and provides an update on ICI-related AKI, summarising the information from recently published clinical trials, meta-analyses, and systematic reviews. It also examines the recommendations of the major international guidelines, provides practical information for the practising nephrologists and identifies the gaps in the current knowledge to help future research.