AKI in Patients Receiving Chimeric Antigen Receptor T Cells: Risk Factors and Characteristics

Background: Chimeric antigen receptor T-cell (CAR-T) therapy is a breakthrough in hematologic malignancies treatment but carries risks, including acute kidney injury (AKI). This study is intended to report the incidence and characteristics of AKI and potential associated factors in patients receiving CAR-T therapy. Methods: We analyzed 186 patients treated with CAR-T therapy in an academic institution, assessing AKI incidence, timing, severity, and associated risk factors within 100 days post-infusion of CAR-T product. AKI and Chronic Kidney Disease (CKD) were defined per KDIGO criteria and recorded from the day of infusion. Cytokine Release Syndrome (CRS) was graded based on the criteria of the American Society of Transplantation and Cellular Therapy. Chi-square test and Fischer's exact test were used for categorical values. T-Tests done where appropriate. Results: Among 186 patients (103 with multiple myeloma (MM), 75 with non-Hodgkin Lymphoma (NHL), and 8 with leukemia), 34% developed AKI (95% CI: 27%-40.7%) with similar incidence by cancer type. Most cases (77.8%) occurred within three weeks post-infusion. AKI was more common among African American individuals (57.7%, P = 0.015) and with older age compared to those without AKI (mean 67 vs. 62.3 years, P = 0.007). Patients with CKD were more likely to have AKI compared to those without (50.8% vs. 25.6%, P < 0.001). Overall CRS incidence was 82.8% (95% CI: 77.3% to 88.1%), and 35.1% had AKI although no statistical significance found when compared to those without CRS. Higher grades of CRS had higher incidence of AKI (grade 1 = 33.6%; Grade 2 = 36.7%, Grade 3 = 42.9%, P= 0.9). Most AKI episodes were Grade I (68.3%) and reversible; 74.6% recovered baseline kidney function, while 25.8% did not, two died within 100 days, 1 required dialysis. AKI post-infusion was common among patients with prior AKI (50.8%) (P < 0.001). Conclusion: AKI is a frequent and early complication of CAR-T therapy, particularly among African American patients, older individuals, those with CKD and prior history of AKI. While most cases are mild and reversible, further studies are needed to implement measures to potentially mitigate and lower the incidence of AKI in these individuals.