Urine Biomarkers On First Day After Transplant Predict One-Year Outcomes
PHILADELPHIA—Higher urinary levels of two biomarkers on the first day following renal transplantation can predict poor graft function at one year, researchers reported at the 2011 American Transplant Congress.
Previous studies have shown that the biomarkers, neutrophil gelatinase-associated lipocalin (NGAL) and interleukin-18 (IL-18), are associated with delayed graft function and three-month graft function.
Investigators Isaac E Hall, MD, a Clinical Research Fellow at the Yale School of Medicine in New Haven, Conn., and colleagues studied 153 renal transplant recipients who had a mean age of 54 years. The study population was 61% male and 53% white. Donors had a mean age of 39 years; 57% were male and 86% were white. The primary outcome was a composite of return to dialysis or GFR below 30 mL/min/1.73 m2 at one year (death-censored).
During the study, 13 patients died (8%), 11 (7%) returned to dialysis, and 23 (15%) had a glomerular filtration rate. Patients with NGAL and IL-18 levels above median values had a 6.0 and 5.5 times increased risk, respectively, for the composite outcome, after adjusting for donor and recipient age, cold ischemia time, and urine output on post-operative day 1.
The researchers looked at outcomes according to DGF status. The primary outcome occurred in about 25% and 24% of patients with NGAL and IL-18 levels above the median, respectively, and only about 4% or 5% of those with NGAL and IL-levels below the median, differences that were statistically significant. Among patients with DGF, levels of NGAL and IL-18 did not significantly affect the occurrence of the primary outcome.