Urine biomarker levels were measured at the Cincinnati Children's Hospital Medical Center Biomarker Laboratory. Commercially available ELISA kits were used to measure urine IL-18 (Medical & Biological Laboratories Co., Nagoya, Japan), KIM-1 (R & D Systems, Inc., Minneapolis, MN),26 (link) and PIIINP (USCN Life Sciences, Wuhan, Hubei, China). Urine albumin and creatinine were measured by immunoturbidimetry and colorimetric enzyme assay, respectively, using a Siemens Dimension Xpand plus HM clinical analyzer (Siemens, Munich, Germany).