Intraductal Secretin CCK Stimulated Pancreatic Exocrine Function Test for Differentiating Normal and Chronic Pancreas

초록

Introduction. Direct pancreatic function test such as secretin-CCK test with duodenal intubation show high specificity and sensitivity, therefore is accepted as gold standard for the diagnosis and functional assessment of chronic pancreatitis (CP). However, Secretin-CCK test with duodenal intubation are labor intensive and take at least I hour to perform. The development and popularity of endoscopic retrograde cannulation of pancreatic duct allows collection of pure pancreatic juice (PPJ) uncontaminated with bile and duodenal secretions. Recently intraductal secretin-CCK test (IOSCT) in which PPJ was obtained, has been reported, but controversies are remained about optimal test time and normal value for differential diagnosis of CPo Aims: To determine when is optimal test time and which biochemical parameters is required for better discrimination of normal and CP. Methods. PPJ was obtained by endoscopic cannulation of the main pancreatic duct in 15 healthy subjects and 30 patients with CP. Pancreatogram findings of patients with CP were based on the Cambridge (Camb.) classification, and Camb. I, Camb. II, and Camb. III were found in 5,13, and 12 patients, respectively. Samples ofPPJ were collected in six fractions for 30 min at 5-min intervals after an intravenous bolus injection of secretin (0.25CUlkg) and CCK (40nglkg). Volume, bicarbonate, amylase and protein outputs were measured. Lower limit value were calculated by equation (mean value-1.5x S.D). Results. Volume, bicarbonate, amylase and protein outputs were increased at first 5 min and reach peak levels at 1O-15min, after then sustained plateaus in control group. But, protein and amylase output showed wide individual variations. Volume and bicarbonate output were significantly decreased in CP comparing with normal control and magnitudes of impairment in exocrine functions were well correlated with morphologic classification in CP. The low limit values of volume and bicarbonate output at 15min PPJ sample were 5.6ml and 6.3mEq, respectively. The sensitivity and specificity of volume at l5min sample were 61.9% and 100%, and that of bicarbonate at 15min sample were 76.2% and 100%, respectively. Conclusions. IOSCT is useful for assessing exocrine pancreatic function in patients with CP, which has high specificity. These data suggested that a I5-min collections of PPJ with IOSCT provide a quick and reliable method for differential diagnosis of CP and that the best discriminatory parameter is bicarbonate output.