Further studies have demonstrated its diagnostic utility in patients with AKI in the setting of critical illness [10,31] following cardiopulmonary bypass surgery [12,32-34] and after toxin exposure [14,35] IL-6 is another pro-inflammatory cytokine that has been shown to be elevated in animal models of AKI [36] and in humans with AKI after cardiac surgery [37,38] or with severe sepsis [39]. This evidence concerns the gene IL6 and acute kidney injury.