Abnormal renal function tests at presentation in severe COVID 19 pneumonia and its effect on clinical outcomes

Abstract

AimTo determine the incidence of abnormal renal function tests at presentation in South Asian patients admitted with severe COVID 19 pneumonia and determine its effect on disease severity and clinical outcomesMethodsThis was a retrospective cross-sectional study conducted at the COVID Intensive care unit of a large tertiary care government hospital in Karachi, Pakistan. 190 patients admitted over five months from 1/5/2021 till 30/6/2021 were included in the study. Patient demographic characteristics, comorbidities, and clinical manifestations of COVID 19 infection were recorded. Laboratory values at the time of presentation, including Hemoglobin, NLR, platelets, blood urea nitrogen, glomerular filtration rate (GFR), inflammatory markers, liver function tests, and electrolytes were recorded. Patient outcome and need for mechanical ventilation were assessed 28 days after admission and compared with the incidence of abnormal renal functions at presentation.ResultsMean GFR and BUN at presentation were 69.7 and 28.4 respectively. 109 (50.4%) patients had abnormal renal function tests at the time of presentation. 76 (40.0%) patients had low GFR and 33 (17.4%) had only raised BUN with normal GFR. Mean GFR was lower in non-survivors vs survivors (p-value 0.000) and in patients who required mechanical ventilation (p-value 0.008). Patients who had low GFR showed greater mortality than those with normal GFR (p-value 0.04) and were more likely to require mechanical ventilation (p-value 0.04).ConclusionLow GFR at presentation is common in patients with severe COVID 19 pneumonia and is associated with a higher in-hospital mortality rate and need for mechanical ventilation.