Predictability of clinicobiochemical scoring systems for early identification of severe gallstone-associated pancreatitis.
Early identification of severe gallstone-associated acute pancreatitis (GAAP) is a prerequisite for treatment with urgent endoscopic sphincterotomy. This study assesses the value of two clinicobiochemical scoring systems to this end. Over the 7-year period from 1983 to 1989, 100 consecutive patients with acute pancreatitis (45 related to gallstones, 36 to alcohol, and 19 of undetermined etiologies) had clinicobiochemical analysis within 48 hours of admission. The final diagnosis and outcome were retrospectively compared with the prediction achieved by the scoring systems. With regard to Blamey's criteria for early identification of gallstones, significant differences were found between the biliary and nonbiliary groups with respect to female sex, serum amylase concentration greater than or equal to 4,000 IU/L, alkaline phosphatase level greater than or equal to 300 IU/L, and alanine aminotransferase level greater than or equal to 100 IU/L (all p values less than 0.001). Age greater than or equal to 50 years was found to be significant (p less than 0.02) only in differentiating gallstone- versus alcohol-associated acute pancreatitis. When three or more positive factors were present, the sensitivity and specificity for predicting gallstones were 60% and 87%, respectively; the predictive value of a positive result was 79%, of a negative result 74%, and the overall accuracy was 75%. At a cutoff level of five, rather than three or more prognostic factors, the modified Ranson's criteria for patients known as having GAAP allowed a suitable discrimination of patients with an expected high risk of complications and mortality. When the two scoring systems (Blamey greater than or equal to 3 and Ranson greater than or equal to 3) were combined, 17 patients were predicted as having severe GAAP: 6 of these 17 patients were misdiagnosed as having biliary pancreatitis, whereas 9 patients with definite severe GAAP were not selected because of a Blamey score less than 3. More specific diagnostic tools are needed, and higher cutoff levels for prognostic scores are required for the prediction of severe GAAP, particularly in view of selecting patients for potentially dangerous approaches such as urgent endoscopic sphincterotomy.