Acute Kidney Injury after CAR-T Cell Therapy: Low Incidence and Rapid Recovery

Chimeric antigen receptor (CAR) T cell therapy using engineered cytotoxic T cells has shown promising responses in various hematologic malignancies. Cytokine release syndrome (CRS) and immune effector cell-associated neurologic syndrome (ICANS) are recognized toxicities of CAR-T, whereas kidney injury remains less well recognized. The objective of the present study was to identify the incidence of acute kidney injury (AKI) after CAR-T cell therapy, potential risk factors, and recovery of kidney function. We performed a retrospective review of 46 adult patients with non-Hodgkin lymphoma treated with CAR-T therapy between February 2018 and February 2019 at our institution. Serum creatinine values before CAR-T therapy through day 100 were used to assess AKI, as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria: grade 1, 1.5- to <2-fold of baseline; grade 2, 2- to <3-fold of baseline; grade 3, ≥3-fold of baseline. CRS and ICANS were graded using the consensus criteria of the American Society of Transplantation and Cellular Therapy. The overall incidence of CRS was 78.3% (95% confidence interval [CI], 66% to 90.5%), of whom 13% (95% CI, 3.3% to 22.8%) developed grade 3-4 CRS, whereas the overall incidence of ICANS was lower at 45.7% (95% CI, 3.1% to 60.3%). The cumulative incidence of any grade AKI by day 100 was 30% (95% CI, 16.9% to 43.9%), with a grade 1 AKI incidence of 21.7% (95% CI, 9.7% to 33.8%) and a grade 2-3 AKI incidence of 8.7% (95% CI,. 4% to 17%). No patients developed severe AKI necessitating renal replacement therapy. Patients with previous autologous or allogeneic stem cell transplantation, those requiring intensive care unit level care and with grade 3-4 CRS had a higher incidence of AKI. Most patients recovered, with kidney function returning to baseline within 30 days. We conclude that with early recognition and management of CAR-T complications, the incidence of AKI is low, the severity of injury is mild, and most patients recover kidney function within 30 days.