Sepsis-Associated Acute Kidney Disease

Abstract Introduction About one third of critically ill patients with acute kidney injury (AKI) develop persistently decreased kidney function, known as acute kidney disease (AKD), which may progress to chronic kidney disease (CKD). Although sepsis is the most common cause of AKI, little is known about sepsis-associated AKD. Methods Using data from a large randomized trial including 1,341 patients with septic shock, we studied patients with stage 2 or 3 AKI on day 1 of hospitalization. We defined AKD as a persistently reduced GFR for >7 days. In addition to clinical data, we measured several urinary biomarkers (TIMP-2*IGFBP7, NGAL, KIM-1, L-FABP, and type 4 collagen) at 0, 6, and 24 hours to predict AKD. Results Of 598 patients, 119 (19.9%) died within 7 days, 318 (53.2%) had early reversal of AKI within the first 7 days, whereas 161 (26.9%) developed AKD. In patients with early reversal, 45 (14.2%) relapsed AKI after early reversal and only about a third of these recovered. Among patients developing AKD, only 15 (9.3%) recovered renal function prior to discharge. Male sex, black race and underlying CKD were more predominant in patients developing AKD. None of the biomarkers tested performed well for prediction of AKD, although NGAL modestly increased the performance of a clinical model. Conclusion AKD is common in patients with septic shock especially among African-American males and those with underlying CKD. Existing AKI biomarkers have limited utility for predicting AKD but might be useful together with clinical variables. Novel predictive biomarkers for renal recovery are needed.