Rates of AKI in ICU Patients Admitted Under Suspicion for COVID-19 Do Not Differ by SARS-CoV2 Status or SARS-CoV-2 Genomic Load

Abstract

Rationale: Since the onset of coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), studies have suggested a high incidence of acute kidney injury (AKI) among patients with COVID-19. However, these studies lack contemporaneously enrolled critically ill patients to understand whether high rates of AKI are unique to COVID-19. It is also unknown whether the risk of AKI is related to SARS-CoV-2 genomic load. Methods: We prospectively enrolled a cohort of patients admitted to the ICU with suspicion of COVID-19 (persons under investigation) from April to September 2020. Of these patients, 78 (46%) tested positive for SARS-CoV-2 (COVID-19) and 91 (54%) tested negative (non-COVID-19). AKI was defined as an increase ≥ 0.3 mg/dL in 48 hours or ≥ 50% increase in serum creatinine (sCr) measured during hospitalization compared to a 'baseline' sCr measured at study enrollment. New dialysis was defined as initiation of dialysis during hospitalization. SARS-CoV-2 qRT-PCR was performed across four different platforms with comparable cycle threshold (Ct) values. Ct values were a semiquantitative measure of genomic load with an inverse relationship of Ct to genomic load. We used relative risk regression to determine if there was an increased risk of AKI in COVID-19 compared to non-COVID-19 and whether SARS-CoV-2 genomic load was associated with AKI. Analyses were adjusted for age, sex, body mass index, and APACHE III scores. Results: Rates of AKI and new dialysis were similar in COVID-19 compared to non-COVID-19 (AKI: n=23 (29%) vs n=24 (26%) and Dialysis: n=8 (10%) vs n=6 (6%). Unadjusted and adjusted analyses demonstrated a non-significant difference in risk of AKI (adjusted RR = 1.04 (95% CI: 0.65-1.66) or new dialysis (adjusted RR = 1.55 (95% CI 0.58-4.12) in COVID-19 compared to non-COVID-19. We had Ct values available prior to ICU admission in 47 patients. In unadjusted and adjusted analyses, a 10-unit decrement in Ct values was not associated with AKI (adjusted RR = 0.40 (95% CI: 0.14-1.14) or new dialysis (adjusted RR = 0.96 (95% CI: 0.23-2.69) (Figure 1). Conclusions: Our study demonstrates that rates of AKI and new dialysis in ICU patients with COVID-19 are similar to rates in non-COVID-19 ICU patients. Moreover, the lack of association between Ct values and AKI in COVID-19, suggests that immune and host response to SARS-CoV-2 may contribute more to risk of AKI in ICU patients rather than the pathogen itself.