Department of Internal Medicine, Institute of Gastroenterology Yonsei University College of Medicine, Seoul, Korea
Corresponding author:
Jae Bock Chung,
ABSTRACT
Background/Aims: The serum lipase/amylase ratio has been proposed to distinguish acute episodes of alcoholic from nonalcoholic pancreatitis. We assessed the clinical utility of this ratio in differential diagnosis of etiologies of acute pancreatitis. Methods: We retrospectively reviewed all records with the diagnosis of acute pancreatitis at the Yonsei University Severance Hospital between January 1990 and June 1995. A total of 138 charts were reviewed. For a patient to be included in the subsequent analysis, the following criteria were met: 1) the patient had typical symptoms of pancreatitis, and serum levels of amylase or lipase were elevated, 2) serum lipase and amylase were analyzed within 48 hours of the onset of symptom, 3) serum creatinine was less than 2.5 mg/dL on admission. Twenty one patients satisfied the requirement for inclusion in the study. Data collected from the charts included age, sex, serum amylase and lipase (from this the lipase/amylase ratio was calculated), duration of abdominal pain before admission, length of hospital stay, various laboratory parameters, severity according to the Atlanta classification and positive scores according to Ranson’s criteria. The lipase/amylase ratio was calculated on serum amylase and lipase (expressed as multiples of the upper limit of normal), each of which was obtained at least within 48 hours of the onset of symptom. Eleven patients had acute alcoholic pancreatitis and the remaining 10 patients had acute biliary pancreatitis. Results: All patients with alcoholic pancreatitis were male, while there were 4 male and 6 female patients in biliary pancreatitis group. There was no difference in the serum amylase, lipase and lipase/amylase ratio (p=0.4813) between the two groups. The sensitivity of a lipase/amylase ratio of >2.0 in detecting acute alcoholic pancreatitis was 81.8%, the specificity was 0%. The sensitivity and specificity of a ratio of >3.0 were same to those of a ratio of >2.0. The serum levels of aspartate aminotransferase and alkaline phosphatase were significantly higher(p=0.0004, 0.0003) and hospital stay was much longer(p=0.0198) in patients with biliary pancreatitis than in those with alcoholic pancreatitis. But there was no significant difference in duration of symptoms, Ranson scores, severity and other clinical parameters between the two groups. Conclusion: The lipase/amylase ratio is not useful in distinguishing acute episodes of alcoholic from acute biliary pancreatitis.