Predictive factors for severe evolution in acute pancreatitis and a new score for predicting a severe outcome

BACKGROUND Acute pancreatitis (AP) is an acute inflammation of the pancreas with an unpredictable evolution. The aim of this study was to assess the factors associated with severe evolution of AP and to create a new score for predicting a severe outcome. METHODS The initial group included 334 patients hospitalized in 2006-2009. The validation group included 195 patients admitted in 2010-2011. AP was classified according to the Atlanta criteria. RESULTS In the initial group, C-reactive protein (CRP), creatinine, white blood count, body mass index (BMI), age and male gender were correlated with severe evolution of AP. Using only parameters available in emergency, by multiple regression analysis we obtained in the initial group the following score for predicting severe evolution of AP: Prediction pancreatic severity I score (PPS I score) = -1.038 + 0.119 × creatinine (mg/dL) + 0.012 × BMI (kg/m²) + 0.027xwhite blood count/1000 (cells/mm³) + 0.195 × gender (1-women, 2-men) + 0.005 × age (years). For a cut-off value >0.325, PPS I score had 71.8% accuracy (AUC=0.790) for predicting a severe evolution of AP. In the validation group the accuracy was 71.7%. Since CRP was proven to be a good predictor of severe evolution in AP, we calculated another score, PPS II, obtained using PPS I and CRP: PPS II score = -0.192 + 0.760 x PPS I + 0.003 x CRP (mg/L). For a cut-off value >0.397, PPS II score had 87.1% accuracy (AUROC=0.942) in the initial group and 75.3% accuracy in the validation group for predicting severe AP. CONCLUSIONS PPS I and especially PPS II score are accurate predictors of severe outcome in patients with AP.