Karras A, Livrozet M, Lazareth H, et al. - Patients with coronavirus disease 2019 (COVID-19) frequently exhibit kidney involvement, and have higher mortality in correlation with occurrence of AKI. Researchers conducted a single-center retrospective study with the aim to report the occurrence and significance of proteinuria in this setting. Among 200 patients with available data, 84 (42%) had urine protein-creatinine ratio of ≥ 1 g/g at admission, although most patients had normal kidney function, with a median serum creatinine of 0.94 mg/dl. Per findings, patients admitted for COVID-19 very frequently exhibit proteinuria which may precede AKI. They indicated low levels of albuminuria are suggestive of a predominant tubular origin, as confirmed by the increased levels of urine retinol binding protein. A strong correlation of urine protein-creatinine ratio ≥ 1 g/g at admission was observed with poor kidney and patient outcome.