Clinical and Biochemical Characteristics of COVID-19-Associated Acute Kidney Injury (COVAKI): A Proof-of-Concept Case-Control Study.

Introduction Acute kidney injury (AKI) develops in 20-70% of patients with COVID-19. AKI is a syndromic diagnosis with multiple causes and outcomes. This cross-sectional study explored different outcomes of AKI in patients admitted with COVID-19. Material and methods It was a cross-sectional and descriptive study carried out in a tertiary care teaching hospital in Western Maharashtra for two months (May to June 2020). We collected clinical and laboratory data of 456 inpatients admitted with COVID-19 over two consecutive months. We excluded patients already on dialysis upon arrival at the hospital. It predominantly consists of patients who developed AKI during their stay in the hospital. Result C-reactive protein (CRP) was elevated in patients with COVID-19 associated with AKI (COVAKI) (78.87) but was statistically significant (p<0.003). Ferritin was elevated significantly (1619.19) in patients with AKI (p<0.0001). Similarly, higher levels of D-dimer (426.35) and lower serum albumin (1.86) were associated with COVAKI (p<0.0001). The average ICU stay was six days for patients with AKI and 0.37 days for patients without AKI. Days on the ventilator were 3.3 days for patients with AKI and 0.11 days for non-AKI patients. Out of a total 12 deaths of COVID-19 patients over these two months, nine had AKI. This made the association statistically significant (p<0.0001). Conclusion The phenotype COVAKI was associated with higher inflammatory markers, prolonged hospital stay, days spent on a ventilator, and higher oxygen requirement translating into higher mortality compared to those without COVAKI. We found low serum albumin without a corresponding proteinuria or liver dysfunction. The development of COVAKI during the hospital stay was associated with the use of glucocorticoids, hydroxychloroquines (HCQs), and heparin.