Dimension xpand plus hm clinical analyzer

The outcomes of this study were urine levels of four biomarkers: IL-18, KIM-1, PIIINP, and ACR. Biomarker levels were measured at the Cincinnati Children’s Hospital Medical Center Biomarker Laboratory. Urine IL-18 was measured using a commercially available ELISA kit (Medical & Biological Laboratories Co., Nagoya, Japan). The urine KIM-1 ELISA was constructed using commercially available reagents (R & D Systems, Inc., Minneapolis, MN).^{22 (link)} Urine PIIINP was measured by a commercially available ELISA (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). Coefficients of variation for the urine measurements were: IL-18, 7.2%; KIM-1, 5.2%; PIIINP, <10%; albumin, 5.9%; and creatinine, 4.1%. Urine specimens were in continuous storage at −80°C until biomarker measurement without prior freeze-thaw. Laboratory personnel performing the biomarker assays were blinded to participants’ clinical information.

Primary predictors in this study were urine concentrations of albumin, KIM-1, and IL-18, all of which were measured concurrently from previously frozen stored urine samples and indexed by the concurrent urine creatinine concentrations (denoted as ACR, KIM-1:Cr, and IL-18:Cr, respectively). All urine biomarkers were measured at the Cincinnati Children’s Hospital Medical Center Biomarker Laboratory. Albumin and creatinine were measured by immunoturbidimetry and colorimetric enzyme assay, respectively, using a Siemens Dimension Xpand plus HM clinical analyzer (Siemens, Munich, Germany). The KIM-1 enzyme-linked immunosorbent assay (ELISA) was constructed using commercially available reagents (R&D Systems Inc, Minneapolis, MN).^{12 (link)} IL-18 was measured using a commercially available ELISA kit (Medical & Biological Laboratories Co Ltd, Nagoya, Japan). Coefficients of variation for the urine measures were albumin, 5.9%; creatinine, 4.1%; IL-18, 7.2%; and KIM-1, 5.2%.