Abstract:Objective To investigate risk factors of the development of infected pancreatic necrosis in the late course of severe acute pancreatitis (SAP). Methods The clinical data of 205 patients with SAP treated in our hospital from January 2011 to May 2015 were retrospectively analyzed. According to the presence of infected pancreatic necrosis, the patients were divided into two groups: infection group and non-infection group. The risk factors of the disease were evaluated. The receiver operating characteristic (ROC) curves for the significant parameters were generated to assess their sensitivities and specificities for diagnosis of the infected pancreatic necrosis. Results 76 cases of the 205 patients with SAP were appeared infectious pancreatic necrosis, and the incidence was 37.1 %. The C-reactive protein (CRP), procalcitonin (PCT) and APACHE II score in the infected group were significantly higher than the non-infected group (P < 0.05). The ROC curve analysis showed that area under the ROC curve of CRP, PCT and APACHE II were 0.861, 0.809 and 0.804, their correspondent cut-off value 235.5 mg/L, 7.5 ng/ml and 15.5, sensitivity 81.7 %、81.1 % and 89.0 %, specificity 77.9%, 70.6% and 68.4 %, respectively. Conclusion The elevated abnormally of CRP, PCT and APACHE II have major detective value for the development of infected pancreatic necrosis in the late course of SAP.