ABSTRACT
BACKGROUND AND AIMS: The objectives of the present study are to compare the renal impairment between patients with SARS-COV-2 in two different time periods with dominant beta and delta SARS-COV-2 variants, with or without prior chronic kidney disease (CKD). METHOD: The study was performed on 80 patients from Bucharest Emergency University Hospital, Nephrology ward, 40 out of 80 patients were diagnosed with SARS-COV-2, beta variant dominant and 40 were diagnosed with SARS-COV-2 delta variant dominant. All patients were confirmed with SARS-COV-2 infection with positive PCR tests. In order to assess the renal function for the patients with beta and delta variant of SARS-COV-2, the values of urea, creatinine, sodium, potassium, calcium, phosphorus and haemoglobin were observed during their hospitalization. Only 4 out of 40 patients with beta variant (10%) had documented pre-existing CKD. The average period of hospitalization was 14 days, with three exceptions (7.5%) in which due to the advancement of acute respiratory failure patients were transferred to the ICU. Only 3 out of 40 patients with delta variant (7.5%) were diagnosed with acute kidney injury (AKI). Average period of hospitalization was 14 days, with three exceptions (7.5%) in which due to the advancement of acute respiratory failure patients was transferred to the ICU. RESULTS: In 36 out of 40 patients (90%) with beta variant dominant of SARS-COV- 2, the analysis of biological parameters shows a minimal change in their values during hospitalization with normal maintenance of renal function. In two patients (5%), diagnosed with CKD, an average of three to four haemodialysis sessions were performed with the improvement of renal function, while maintaining a minimum nitrogen retention. In two patients with CKD (5%), renal function depreciated, leading to haemodialysis initiation. In 33 out of 40 patients (82.5%) with delta variant dominant of SARS-COV-2, the analysis of biological parameters shows a minimal change in their values during hospitalization with normal maintenance of renal function. In 4 out of 40 patients (10%), the renal function depreciated in context of multiple system organ failure (MSOF), and subsequently they died. During hospitalization, in three patients (7.5%) who were admitted with AKI, the renal disfunction was resolved by the time of their discharge. There were no statistically relevant differences (P > .1) in measured parameters between the two time periods with the different SARS-COV-2 strings. CONCLUSION: According to this statistical analysis, the delta variant does not cause more kidney damage than the beta variant of SARS-COV-2. For the six patients (7.5%) with renal impairment, two from the beta batch (2.5%) and four from the delta batch (5%), the suspicion of renal damage in SARS-COV-2 infection may be raised, but excluding other causes of renal damage is necessary. For the three patients (7.5%) with AKI from the delta batch, the suspicion of renal damage caused by COVID-19 may be raised because there were no other causes for renal impairment.