Coronavirus disease 2019-induced acute kidney injury: a retrospective single-center study

Abstract Background Acute kidney injury (AKI) is a frequent complication in patients with severe coronavirus disease 2019 (COVID-19), contributing to increased mortality and longer hospital stays. This study investigates the effects of tocilizumab (TCZ) on renal function in such patients. Patients and methods A retrospective analysis was conducted on 250 patients with confirmed severe COVID-19. Daily monitoring of renal indicators was performed. Those with suspected cytokine storm—indicated by raised interleukin-6 or C-reactive protein levels greater than 75 mg/l—received TCZ at 4–8 mg/kg (up to 800 mg), either once or in repeated doses. Results Renal impairment and electrolyte disturbances were significant after admission ( P =0.001). AKI developed in 52% of patients, and 8% required continuous renal replacement therapy. Urine analysis revealed hematuria in 10%, proteinuria in 28%, and normal findings in 62%. Comorbidities included diabetes and hypertension (each in 40% of patients), CKD (16%), ischemic heart disease (14%), asthma (6%), and hypothyroidism (4%). TCZ administration led to marked improvement in renal parameters and electrolytes ( P =0.001). Conclusion AKI is common in severe COVID-19 cases and may signal worse outcomes. Routine monitoring of kidney function is crucial. TCZ may offer indirect renal protection in COVID-19-associated AKI, especially when used early in cytokine storm.