Urine samples were collected for analysis of urinary neutro- phil gelatinase-associated lipocalin (uNGAL). Urine NGAL measurements were performed using a commercially available enzyme-linked immunosorbent assay (Bioporto, Gentofte, Denmark) as published previously.18–20 The intra-assay and inter-assay coefficients of variability are 5.6% and 6.4%, respectively. The lower limit of detection of the assay is 6.5 pg/mL.