Ranson's Criteria for Acute Pancreatitis in High Altitude: Do they Need to be Modified?

BACKGROUND/AIM: To examine the validity of Ranson's criteria in the prediction of the severity of acute pancreatitis (as judged by the occurrence of complications) in a high-altitude area of Saudi Arabia with a predominant biliary pancreatitis. MATERIALS AND METHODS: All consecutive cases of acute pancreatitis (AP) admitted to a tertiary care hospital over a two-and-half-year period were included in this prospective study. Ranson's criteria (RC) were used to determine the severity of the attack of AP, which was then correlated with the occurrence of complications. The validity of Ranson's score and that of each of its individual components was estimated. Using receiver operating characteristic (ROC) curve, new optimum values for these components were calculated and a new modified score was constructed. RESULTS: Seventy-three attacks of AP in 69 patients formed the material of this study. Ranson's prediction criteria classified 43.8% of the attacks as “severe”, but only 22% of those attacks were associated with complications. Calcium level (<8 mg/dl) was the only criterion that was significantly associated with complications (Kappa = 0.32, P = 0.02). Using ROC curve to determine the optimum cut-off levels for prediction identified only four criteria, which were significantly associated with complications as compared with the original Ranson's cut-off levels. Those were: a serum glucose value of ≥160 mg/dl (P < 0.05), blood urea nitrogen rise of ≥35 mg/dl (P < 0.02) and an arterial Po(2) value of ≤55 mm Hg (P < 0.01), in addition to calcium value of <8 mg/dl (P = 0.02) as originally set by Ranson. A new scoring system, ranging from 0 to 4, based on these cut-off levels, together with a calcium level of <8 mg/dl, could correctly classify the severity of AP. A total score of two or more points predicted a severe attack with a sensitivity of 88%, a specificity of 82% and a Kappa coefficient of 0.47 (P < 0.001). CONCLUSION: This study showed that Ranson's criteria may need to be modified in high altitude with a predominant biliary pancreatitis in order to accurately predict the severity of AP.