Acute Kidney Injury and Electrolyte Disorders Following Chimeric Antigen Receptor T-cell (CAR T-cell) Therapy in Adults With Hematologic Malignancies: A Retrospective Study

Introduction Renal complications are increasingly recognized after chimeric antigen receptor (CAR) T-cell therapy. We evaluated the incidence and severity of acute kidney injury (AKI), the prevalence of electrolyte disturbances, and clinical factors associated with AKI in adult patients with hematological malignancies. Methods We retrospectively reviewed all adult patients with hematological malignancies who received CAR T-cell therapy at a single tertiary center between November 2023 and April 2025. Baseline demographics, comorbidities, prior therapies, and post-infusion events were collected from electronic medical records. AKI was defined and staged according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines based on serum creatinine (Cr) levels. Electrolyte disturbances (sodium, potassium, and phosphate) occurring within 100 days post-infusion were recorded. Data were analyzed using R statistical software (version 4.5.1). Continuous variables are presented as the mean ± SD or median (IQR). Groups were compared using t-tests, Wilcoxon rank-sum tests, and Fisher's exact tests. Associations between AKI and patient characteristics were assessed using logistic regression. Hospitalization outcomes were evaluated using Kaplan-Meier and Cox proportional hazards models. A p-value < 0.05 was considered statistically significant. Results This study included 16 patients (mean age: 56.7 ± 17.7 years; 50% male), 25% of whom developed AKI (all stage 1). Pre-existing chronic kidney disease (CKD), baseline Cr ≥75 μmol/L, and diabetes mellitus showed the strongest associations with AKI. Electrolyte disturbances were common, particularly potassium and phosphate abnormalities. AKI was not significantly associated with ICU admission, longer hospitalization, or early mortality. Conclusion In this cohort, renal events after CAR T-cell therapy were mainly mild. Pre-existing CKD and diabetes mellitus were associated with an increased risk of AKI. Therefore, we suggest close monitoring of kidney function and other risk factors (such as nephrotoxic medications, contrast exposure, and dehydration) during treatment. Further studies with larger cohorts and longer follow-up are required to clarify the mechanisms of renal impairment and better assess outcomes.