AKI results from an abrupt loss of kidney function and is strongly associated with increased mortality and morbidity.12 We found that patients with elevated serum creatinine were more likely to develop AKI during hospitalization, which is consistent with study in SARS.5 It is therefore important to increase the awareness of AKI in those who entered the hospital with an elevated serum creatinine. In our cohort, the detection rate of AKI in patients with COVID-19 was 5.1%, which is in keeping with recent reports of small sample size1 , 4 , 7 , 13 and much higher than the 0.5% of a large observational study.14 This may be explained by an extremely high proportion of severely sick patients in a previous case series and only 15.7% in the large observational study. In our cohort study, 42.7% of patients were severely ill, and this may explain the higher detection rate of AKI in clinic practice in Wuhan. Importantly, the present method of detecting AKI is mainly based on acute changes in serum creatinine and the frequency of serum creatinine tests has a substantial impact on detection rate.15 In a nationwide cross-sectional survey of hospitalize adult patients in China, the detection rate of AKI was only 0.99% by Kidney Disease: Improving Global Outcomes (KDIGO) criteria.16 After adjusting for the frequency of serum creatinine, determinations of the incidence of AKI in Chinese hospitalized adults rose to 11.6%.17 Thus, to improve early detection of kidney injury, more frequent serum creatinine measurements should be performed in patients with COVID-19.