A brief review of renal-limited thrombotic microangiopathy associated with immune checkpoint inhibitors

Abstract

As a rare immune-mediated adverse reaction to immune checkpoint inhibitor (ICI) therapy, immune checkpoint inhibitor associated renal-limited thrombotic microangiopathy (ICI-rTMA) is a biopsy-proven kidney-limited TMA without the classical triad of systemic TMA. With the expanding use of ICIs, reports of ICI-rTMA are limited yet emerging. ICI-rTMA currently has a poor renal prognosis and a lack of treatment strategy. Furthermore, ICI re-challenge poses a difficult clinical dilemma wherein renal function must be maintained without risking the higher mortality associated with ICI withdrawal. This review summarizes six reported cases of ICI-rTMA and discusses the current literature on ICI-rTMA regarding its potential mechanisms of pathogenesis, the vital role of kidney biopsy in diagnosis, treatment options, and the dilemma surrounding ICI re-challenge.