A group from Université Côte d’Azur, Nice, etc. has reported that Proteinuria would be a good Biomarker for the new coronavirus (COVID-19) severity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7985082/
Significant proteinuria (>0.3 g/g) was related to
higher prevalence of ICU admission [OR = 4.72, IC95 (1.16–23.21), p = 0.03],
acute respiratory distress syndrome (ARDS) [OR = 6.89, IC95 (1.41–53.01, p = 0.02)],
longer hospital stay [19 days (9–31) versus 7 days (5–11), p = 0.001].