Where have all the dreiling tubes gone?

The direct measurement of pancreatic function remains the best tool for diagnosing chronic pancreatitis, especially if imaging tests are normal or inconclusive. The most effective means of measuring pancreatic function is the standard hormone stimulation test using secretin. Traditionally, direct pancreatic function testing involves the fluoroscopic placement of an oroduodenal tube and collection of duodenal fluid containing pancreatic secretions after administration of a standardized dose of secretin and/or CCK. The test is time-consuming and tedious to perform, and placement of the oroduodenal tube is often difficult for the person performing the test and uncomfortable for the patient. Bicarbonate concentration typically has been measured by back-titration, requiring specialized equipment no longer found in most hospital clinical chemistry laboratories. For these reasons, the direct testing of pancreatic function after secretin stimulation has become a much admired but rarely performed test, currently done in only a few centers in the United States. In this issue of the Journal, Stevens et al. report on a cross-over study of secretin-stimulated endoscopic pancreatic function test (ePFT) and dreiling tube pancreatic function test (D-PFT) in healthy subjects and demonstrate that the accuracy of the ePFT is comparable to that of the D-PFT (17). They have demonstrated the relative simplicity and reliability of ePFT, bringing it closer to the diagnostic armamentarium of the practicing physician. We may have lost the Dreiling tube but, in its place, gained a "gold standard" which will be more widely used.