Does combining urine sediment examination to renal cell arrest and damage biomarkers improve prediction of progression and mortality of sepsis associated acute kidney injury?

Background: Sepsis associated acute kidney injury (SA-AKI) among hospitalized patients is common with higher morbidity and mortality. There is a need to discover new methods that allow better prediction of its outcomes and prognosis. We aimed to evaluate if combining serial examination of urine sediment to renal cell damage (KIM-1) and arrest (TIMP-2, IGFBP7) biomarkers could improve the prediction of progression and mortality of SA-AKI.

Methods: This prospective study enrolled 96 patients with stage 1 or 2 SA-AKI. Measuring of urinary TIMP-2, IGFBP7 and KIM-1 was done at time of AKI diagnosis and examination of urine sediment was performed by calculating Chawla score (CS) and Perazella score (PS) at days 1, 3 and 7. Main study outcomes included AKI progression to stage 3 and mortality.

Results: Ninety-six patients were included in the study. 48% of them progressed to AKI stage 3 and 33.3% died. uTIMP2*IGFBP7 and uKIM-1 showed an area under the curve (AUC) of 0.837 and 0.657 respectively for predicting AKI progression and an AUC of 0.679 and 0.626 respectively for predicting mortality. Combining urine sediment examination at day 3 (P2 and C2) to uTIMP2*IGFBP7, uKIM-1 and both biomarkers significantly improved their prediction ability to an AUC of to 0.977, 0.951 and 0.979 respectively to predict AKI progression, and to an AUC of 0.807, 0.796 and 0.803 respectively to predict mortality.

Conclusions: Combining urine sediment examination with renal cell damage and arrest biomarkers significantly improved their performance of predicting AKI progression and mortality in patients with SA-AKI.

Clinical trials registration: ClinicalTrials.gov Identifier: NCT06064487. First registration date: 21/09/2023.