Urine Test Predicts Heart Failure Patients' Risk of Kidney Injury

Levels of a protein in the urine may help clinicians predict which patients with acute heart failure are at increased risk of developing kidney injury during hospitalization.

Urinary angiotensinogen levels at the time of hospital admission predicted acute decompensated heart failure patients' risk of developing acute kidney injury with considerable accuracy and help clinicians predict patients' risk of being re-hospitalized or dying within one year.

Scientists at the Southern Medical University (Guangzhou, China) conducted a study in 436 patients with acute decompensated heart failure (ADHF) to validate a new marker, urinary angiotensinogen (uAGT), for predicting patients' risk of developing acute kidney disease (AKI). The primary objective was to test and validate the hypothesis that daily measures of uAGT during the first week of admission predict the development of AKI and one year prognosis in these patients. Spot urine and blood samples were collected immediately after admission before any in-hospital treatment and every 24 hours for the first seven days during hospitalization.

A sandwich enzyme-linked immunosorbent assay (ELISA) kit (Immuno-Biological Laboratories Co., Ltd.; Fujioka, Japan) was used for quantifying AGT in urine and plasma. Standard Western blot analyses with an affinity-purified goat polyclonal antibody against human AGT were used to quantify uAGT. To compare the predictive performance of uAGT and reported renal injury markers, urinary neutrophil gelatinase-associated lipocalin (NGAL) was measured with an ELISA kit (Antibody Shop; Utrecht Netherlands). Creatinine levels were measured using an automatic AU 480 biochemical analyzer (Beckman Coulter, Inc.; Brea, CA; USA).

The team demonstrated that uAGT levels at the time of hospital admission predicted AKI risk with considerable accuracy. The highest quartile of uAGT on admission was linked with a 50-times increased risk of AKI compared with the lowest quartile. Patients' uAGT level at the time of admission also helped clinicians predict patients' risk of being re-hospitalized or dying within one year.

Fan Fan Hou, MD, PhD, a senior author of the study, said, “Our results raise the possibility that by using sensitive and specific biomarkers such as uAGT, clinicians may be able to identify ADHF patients at high risk of developing AKI as early as on the first day of admission. If confirmed, uAGT levels on the first day of admission may improve clinicians' ability to assess ADHF patients' risk of developing AKI and to predict their one-year prognosis, which in turn would help clinicians to plan and initiate the most appropriate management strategies during hospitalization and post discharge.” The study was published on February 26, 2015, in the Journal of the American Society of Nephrology.

Related Links:
Southern Medical University
Immuno-Biological Laboratories Co., Ltd.
Beckman Coulter, Inc.