ALB and infection: The severity of initial infection, AKI development during admission, blood urea nitrogen increase more than 8 units above the threshold, creatinine increase with more than 23 μmol/L during admission, and urine albumin to creatinine ratio increase to more than 11 units above the threshold during COVID-19 admission were identified as key predictors of renal function decline with more than 30 units of eGFR six months post discharge.