Renal Injury by SARS-CoV-2 Infection: A Systematic Review

BACKGROUND: SARS-CoV-2 infection can cause renal involvement, and severe renal dysfunction is more common among patients with chronic comorbid conditions, especially patients with chronic kidney disease. Angiotensin-converting enzyme 2 (ACE2) has been proven to be the major receptor of SARS-CoV-2 in kidneys, suggesting that ACE2-related changes may be involved in renal injury during the infection. In this review, we systematically reviewed the literature to summarize findings on the mechanism of renal injury caused by SARS-COV-2 infection, in order to provide a theoretical basis for renal protection therapy. SUMMARY: For patients with SARS-CoV-2 infection, renal injury mainly manifests as increased serum creatinine, variable degrees of proteinuria and hematuria, and radiographic abnormalities of the kidneys. In this review, we summarize the pathogenesis of renal injury deriving from SARS-CoV-2 infection by focusing on its etiology, pathology, and clinical manifestations. The virus causes kidney injury by either direct infection or systemic effects, including host immune clearance and immune tolerance disorders, endothelium-mediated vasculitis, thrombus formation, glucose and lipid metabolism disorder, and hypoxia. KEY MESSAGES: Renal injury by SARS-CoV-2 is the result of multiple factors. Via highly expressed ACE2 in renal tissue, SARS-CoV-2 infection fundamentally initiates a mechanism of renal injury. Systemic effects such as host immune clearance and immune tolerance disorders, endothelial cell injury, thrombus formation, glucose and lipid metabolism disorder, and hypoxia aggravate this renal injury.