#5618 IMPACT OF THE PATHOPHYSIOLOGY OF ACUTE KIDNEY INJURY IN PATIENTS AFFECTED BY COVID-19 ON CLINICAL OUTCOMES DIALYSIS AND DEATH
Authors: Cardoso Pedro Andriolo , Yuasa Bruna , Magalhães Luis , Oliveira Paula , Favarin Ana , Zamoner Welder , Ponce Daniela 
Published: June 2023

Abstract

Background and Aims
The Coronavirus Disease-19, COVID-19 caused by the Sars-Cov-2 virus has been associated with either asymptomatic and mild conditions or severe acute respiratory syndrome with generalized organ dysfunction and death. One of the most important is Acute Kidney Injury (AKI). It is acknowledged that AKI is multifactorial, as the most relevant factors for its development are the cytokine storm, metabolic stress, medication use, rhabdomyolysis, renal viral tropism, and multiple organ dysfunction. However, little is known about the impact of AKI's pathophysiology on its clinical outcome.

Method
Retrospective cohort study that evaluated the medical records of patients diagnosed with COVID-19 admitted to a Tertiary Public Hospital, from 06/01/2020 to 07/31/2021 from their admission until the outcome. The evaluation of renal function occurred through the variation of urinary output and serum creatinine measurement, and the diagnosis of AKI followed the 2012 KDIGO criteria. The occurrence of AKI was an inclusion criterion in the study. The nephrotoxic drug usage and the leak of clinical and laboratory data were exclusion criteria in the study. In addition to urine output and serum creatinine, the creatine phosphokinase, type 1 urine test concerning proteinuria and haematuria, cardiocirculatory and ventilatory parameters, and vasoactive, diuretic, antihypertensive and corticoid drugs usage were analysed. Univariate analysis was performed to identify whether the pathophysiological mechanisms of AKI (ischemic, cytokine storm- CS, rhabdomyolysis, renal viral tropism, or multiple organ failure- MOF) are associated with death.

Results
Until now, we have included 283 patients. There was a predominance of males (55.5%), Caucasian ethnicity (80.6%); median age was 64 years. Most patients were admitted to the ICU (85.1%). The predominant AKI was KDIGO 3 (56.9%). Regarding the different etiologies of AKI, Renal Viral Tropism was the most frequent (21.5%), followed by MOF (19.1%), Septic (16.6%), Mixed Renal Viral Tropism (16.2%), Ischemic (15.5%) and CS (10,9%). Regarding the CS, patients were more often admitted to the ICU (100%; p&lt;0.001) made the least use of corticosteroids (51.6%; p&gt;0.001) and diuretics (12.9%; p = 0.016), they made the most use of mechanical ventilation (100%), vasoactive drugs (100%) and dialysis (74.2%; p&lt;0.001). Paradoxically, they were the most obese (67.74% p = 0.011), but had less hypertension (48.4%; p = 0.025), less previous cardiovascular disease (6.45% p = 0.01), and less dyslipidemia (9.68%; p = 0.012). In general, the mixed etiology markedly comes closest to the CS etiology, followed by the MOF. Patients who least needed dialysis were those with septic etiology (18.18%; p&lt;0.001). Preliminary tests show an impressive mortality of 69.61%, which is associated with the AKI pathophysiological mechanisms (p&lt;0.0001). CS (87.1%), MOF (87.0%), and Mixed Etiologies (89.1%) are the pathophysiological mechanisms associated with poor prognosis; and Viral Renal Tropism (54.3%), Sepsis (48.3%), and Ischemic Injury (34.1%) are the pathophysiological mechanisms related to the best outcomes.

Conclusion
AKI related to COVID-19 patients are mostly elderly, admitted to ICU, classified as KDIGO 3 and their mortality is notable. Nevertheless, the mortality and the need for dialysis depends on the pathophysiological mechanism their AKI, as CS, MOF, and Mixed Etiologies are the pathophysiological mechanisms associated with poorest prognosis; and Viral Renal Tropism, Sepsis, and Ischemic Injury are related to the best outcomes.