Three urinary biomarkers measured at the time of acute kidney injury (AKI) diagnosis in patients with acute cardiorenal syndrome (CRS) may help to identify those at highest risk for adverse outcomes, investigators concluded in a report published online ahead of print in the Clinical Journal of the American Society of Nephrology.
In a prospective study of 213 with acute CRS and stage 1 or 2 AKI at diagnosis, the highest tertiles of urinary angiotensinogen (uAGT), urinary neutrophil gelatinase-associated lipocalin (uNGAL), and urinary interleukin-18 (uIL-18) were associated, respectively, with a significant 10.8-, 4.7-, and 3.6-fold increased risk of AKI progression, the primary endpoint, compared with the lowest tertiles. After adjusting for clinical variables, uAGT was the best predictor for both AKI progression (primary outcome) and AKI progression with death (secondary outcome), with an area under the receiver operator curve of 0.78 and 0.85.
Addition of the 3 biomarkers to a clinical model that took into account age, gender, hypertension, diabetes, preadmission estimated glomerular filtration rate, and other variables significantly improved risk stratification for AKI progression and AKI progression with death, with uAGT performing the best.
In their cohort, the mortality rate was 36% among patients who presented with stage 1 or 2 AKI and progressed to higher stages compared with 15% in patients who did not progress. “It is therefore critical to identify patients at highest risk of both AKI progression and death so as to guide prognosis and treatment decisions,” the investigators led by Fan Fan Hou, MD, of Southern Medical University in Guangzhou, China, stated. “Unfortunately, the lack of objective tests to predict progression of acute CRS delays initiation of intervention and hinders clinical trials.”
In a discussion of study limitations, the researchers noted that the number of outcomes was relatively small, although there were sufficient events for the primary endpoint. “As is true in the case of most AKI studies, we were not able use urine output for AKI diagnosis because an indwelling urinary catheter was not present in most of the patients.”