COVID-19 and Kidney Disease: A Follow-Up Study

Background: It is well known that SARS-CoV-2 infection is associated with the development of acute kidney disease; however, not much is known about the long-term kidney effects of this pathology. Methods: We analyzed kidney function data during hospitalization and subsequent follow-up (6 months) of 150 (of which 51 with CKD) patients hospitalized for COVID-19. Results: 28% of subjects developed AKI during hospitalization; proteinuria and microhematuria were present in 53% and 40% of subjects respectively. At discharge, 61% of patients had already fully recovered their basal kidney function; the presence of proteinuria and microhematuria was reduced to 4% and 6% at subsequent follow-up. However, looking at the trend of the eGFR during the follow-up, an accelerated reduction in the glomerular filtration rate at 3 and 6 months was observed in subjects with AKI being admitted (73.30±17.08 ml/min vs 62.43±17.13 ml/min at six months; p=0.004). This result was confirmed even after exclusion from the analysis of those patients already known for CKD (eGFR < 60 ml/min) at the time of admission for COVID (eGFR 79.05±14.28 vs 66.17±16.99; p=0.004; figure 1). Conclusions: Starting from these data, we can assume that COVID-19 patients, with intra-hospital AKI development, have an accelerated loss of renal function during follow-up. Further studies are needed to identify pathogenic mechanisms and the long-term evolution of kidney damage after Sars-Cov-2 infection.eGFR: from admission to follow-up