IL9 and acute kidney injury: Future research studies could prospectively enroll participants on ICI therapy and evaluate AIN biomarkers such as interleukin-9 and tumor necrosis factor-α to differentiate ATI from AIN with greater certainty.26 30 Future studies could also evaluate the impact of rapid reintroduction of ICI therapy in those with AKI due to AIN given that these therapies have significant mortality benefit and our preliminary data shows no significant increase in mortality in those predicted to have AIN.