Secretin pancreozymin test
The secretin-pancreozymin test is used in medicine to examine how well the pancreas can produce its digestive juices and release them into the intestine . It is the most reliable method for diagnosing impaired exocrine function of the pancreas ( exocrine pancreatic insufficiency ). However, since it is very time-consuming and expensive, it is only carried out for special questions or as part of scientific studies.
execution
Medication containing pancreatic enzymes must be discontinued at least three days prior to the procedure . After a fasting period of at least twelve hours, a tube is placed through the stomach and into the duodenum . The position must usually be checked by fluoroscopy . The secretion of the pancreas is then drawn off over a quarter of an hour and the content of sodium hydrogen carbonate (bicarbonate) and the activity of the enzymes pancreatic amylase and pancreatic lipase are measured. For the first test stage, a defined amount of the hormone secretin is then injected. The secretion is then withdrawn from the duodenum twice for a quarter of an hour and the bicarbonate concentration is determined. In the second test stage, a defined dose of the hormone pancreozymin (cholecystokinin) is given . Again over a quarter of an hour, the secretion is collected via the lying probe and the activity of the enzymes pancreatic amylase and pancreatic lipase is again determined from these fourth and fifth portions. The volume of each serving must also be noted.
rating
A lack of standardization makes the assessment of the test difficult. Nevertheless, it is considered to be the most reliable method for detecting exocrine pancreatic insufficiency. These are indications of normal ( physiological ) secretion
- a total volume of more than 67 ml / 30 min,
- a bicarbonate secretion greater than 6.5 mmol / 30 min respectively
- a bicarbonate concentration of over 70 mmol / l as well
- a pancreatic amylase secretion of more than 12,000 rpm and
- a pancreatic lipase secretion greater than 65,000 rpm / 30 min.
The test can produce false results if the secretion is not completely collected, is diluted by the influx of gastric acid or flows back into the stomach from the duodenum. The rate of false positives is around 8%, that of false negatives around 6%.
