Kidney manifestations of mild, moderate and severe coronavirus disease 2019: a retrospective cohort study
Daqing Hong, Long Lin, Ying Wang, Lei Yu, Yun Tang, Jia Zhao, Xiaofei Song, Yanan He, Ergang Wen, Ling Zheng, Guisen Li, Li Wang
Abstract
Abstract Background Coronavirus disease 2019 (COVID-19) is a pandemic that has affected more than 3 million patients globally. Previous data from Wuhan city showed that acute kidney injury (AKI), proteinuria and hematuria occurred frequently in patients with severe COVID-19. However, the prevalence of kidney injury in milder cases remains unclear. Methods This retrospective study included two major consecutive cohorts of COVID-19 patients in Sichuan Province. Baseline characteristics, laboratory data including renal function, proteinuria and dipstick hematuria, and other laboratory parameters were collected. A subgroup of patients was followed up for 2–4 weeks to evaluate the short-term outcome of renal impairment. Results Overall, 168 COVID-19-positive patients were included in the study. The majority of patients (79.7%) were diagnosed with mild or moderate disease. Half of patients presented with fever; however, in The Tibetan cohort, fever only occurred in 13.4% of patients. On hospital admission, proteinuria and dipstick hematuria were noted in 18.4% and 17.4% of patients, respectively, while AKI only occurred in one patient. Further analysis showed that severe or critical COVID-19 was associated with higher risk of proteinuria [relative risk (RR) 7.37, 95% confidence interval (CI) 2.45–22.18, P = 3.8 × 10−4] and dipstick hematuria (RR 8.30, 95% CI 2.69–25.56, P = 2.3 × 10−4). Proteinuria, dipstick hematuria, or the combination of proteinuria and hematuria could significantly predict severe or critical severe COVID-19. Conclusions Proteinuria and dipstick hematuria are not uncommon in patients with COVID-19 infection, especially in severe or critical cases.