The same investigators also looked at a cohort of 72 children undergoing cardiac surgery requiring cardio-pulmonary bypass.100 They demonstrated a significant increase in the urinary IL-18 level starting only 4 hours after surgery in the 20 children who developed an acute renal injury (as defined by an increase >50% of baseline creatinine in the 3 days after surgery) when compared to 35 case-controls chosen amongst the 50 children without renal insufficiency. The gene discussed is IL18; the disease is Renal insufficiency.