Urea Creatinine Ratio as a Predictive Marker of Mortality in Acute Kidney Injury in Critical Care? A Study from Tertiary Care Centre

Abstract

Introduction: With increasing prevalence of acute kidney injury, prediction of outcomes is challenging. Though many biomarkers were studied, no single biomarker is labelled as a strong biomarker. Till date, creatinine estimation continues to be reliable marker for diagnosis, prognosis of patients with acute kidney injury (AKI). Availability of simple ratios such Blood urea nitrogen: creatinine has its own fallacies. Another ratio of clinical utility may be urea: creatinine ratio, which is known to be associated with long term mortality. Aim: We assessed the blood urea: creatinine ratio (UCR) as a marker for prediction of mortality in inpatients with AKI Materials and Methods: A prospective study of estimation of admission UCR in all patients with AKI is undertaken in public sector tertiary care teaching hospital. Relation between UCR and mortality, factors influencing the same were analysed. A cut off of UCR that can predict the mortality in patients with AKI was also determined. Results: A total of 451 patients were included in the study. We divided our study group in to three tertiles based on UCR. High tertile group has shown a statistically significant association with age, higher Sepsis-related Organ Failure Assessment (SOFA) score, sepsis with multi organ failure, renal replacement therapy requirements. A cut off value of UCR >46 predicted mortality with specificity of 67% and negative predictive value of 77%. Conclusion: High UCR at admission with cut off >46 is associated with mortality in patients with AKI.