Simultaneous monitoring of multiple urinary cytokines may predict renal and patient outcome in ischemic AKI

Abstract

Acute kidney injury (AKI) is a common disorder associated with high morbidity and mortality rates. Ischemia is the leading cause of AKI. This is a pilot study investigating the ability of multiple urinary cytokines to predict renal functional outcome and mortality in patients with ischemic AKI. Urine samples were obtained from 45 subjects with ischemic AKI on the day of renal consultation and 3 days later. The urinary concentrations of interleukin (IL)-1β, IL-6, IL-8, monocyte chemotactic protein (MCP)-1, interferon-inducible protein (IP)-10, regulated on activation, normal T-expressed and secreted (RANTES), transforming growth factor (TGF)-α, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were measured simultaneously using a microsphere-based immunofluorescence assay. Urinary cytokine levels (pg/mg urine creatinine), which predict renal functional recovery or no recovery the next day and 7 days and 3 months later, were identified. Increased urinary IP-10 and IL-8 predicted no renal functional recovery the next day. Increased urinary IP-10 and VEGF predicted no renal recovery by 7 days. Increased urinary IP-10 and VEGF predicted no renal recovery by 4 days, whereas increased urinary EGF predicted renal functional recovery at that time. Increased urinary IL-8, MCP-1, IP-10, RANTES, EGF, and VEGF predicted patient's death within 3 months. Our findings suggest that urinary IP-10, IL-8, VEGF, TGF-α, and EGF may predict renal functional outcome at various times along the course of ischemic AKI and that urinary IL-8, MCP-1, IP-10, RANTES, EGF, and VEGF may predict mortality of the patients within 3 months.