We aimed at synchronously examining the early time course of 4 proinflammatory cytokines as predictive factors for development of organ failure in patients with acute pancreatitis (AP).Interleukin (IL) 6, IL-8, IL-18, and tumor necrosis factor α were measured on admission and at days 1, 2, and 14 in 60 patients admitted with first attack of AP. The prediction of single-organ and multiorgan failure from the cytokine profiles was evaluated by receiver operating characteristic analyses.Interleukin 6 and IL-8 levels were significantly higher in patients who developed renal, respiratory, and circulatory failure, as was the case for patients with multiorgan failure. Interleukin 18 levels were significantly elevated in renal and respiratory failure only. Tumor necrosis factor α was significantly elevated in all types of organ failures, except for intestinal failure.Synchronous measurements of 4 cytokines demonstrated IL-6 and IL-8 to be predictive as early surrogate markers with regard to organ failures in AP. The fact that all of the cytokines were particularly elevated in patients with organ failures calls for evaluation of agents modifying the severe inflammatory response in patients with AP.