Code Details for Lab and Clinical Services
ISI Order Code:
SCT
CPT Code:
83519
Clinical Significance of Secretin
Secretin is a 27 amino acid basic peptide produced by S-Cells and released by acid delivered into the duodenum. Secretin is released into the blood when duodenal pH drops below 4. Secretin shares structural similarity with Glucagon, Gastric Inhibitory Polypeptide, Vasoactive Intestinal Polypeptide, PHIM, and Growth Hormone-Releasing Hormone. Secretin is a potent stimulus for bicarbonate secretion. Secretin also stimulates secretion of bile, release of Insulin, and release of gastric Pepsin in the stomach. Secretin inhibits Glucagon release, intestinal motility, and prevents the uptake of water and sodium ions by the intestine. In normal patients, Secretin has little effect on Gastrin levels, but stimulates Gastrin greatly in Zollinger-Ellison patients. Secretin may also be elevated in Zollinger-Ellison patients and in patients with duodenal ulcer. Secretin levels are low in patients with pernicious anemia and achlorhydria. Secretin secretion can be suppressed by Somatostatin, Cimetidine, and Methionine-Enkephalin.
Reference Range, Procedure, and Turnaround Time
Reference Range:
12 – 75 pg/ml
Procedure:
Secretin is measured by direct radioimmunoassay.
Expected Turnaround Time:
10 Business Days
Turnaround time is defined as the usual number of days from the date of receipt of a specimen for testing to when the result is released to the ordering facility.Report: Sample Report
Pre-Test Preparation Guidelines
Patient should be fasting for 10 – 12 hours prior to collection of specimen. Antacid medications and medications that affect intestinal motility should be discontinued, if possible, for at least 48 hours prior to collection.
Specimen Collection Instructions
Collect 10mL blood in special ISI GI Preservative tube yielding special GI plasma and separate as soon as possible. Freeze plasma immediately after separation. Special G.I. Preservative tubes are available from Inter Science. Minimum specimen size is 1 ml.
Please contact ISI for separation using a non refrigerated centrifuge. Contact ISI for details.
The Inter Science Institute GI Preservative collection and preservative tube is intended for use with Inter Science Institute’s Cholecystokinin (CCK), Ghrelin, GLP-1, Peptide YY (PYY), Secretin, Somatostatin, and VIP assays only. It has not been validated for use with other in vitro assays. Effects of using this device other than as intended are unknown, and is not recommended.
Important Precautions & Rejection Criteria for Secretin Test
Important Precautions:
Secretin specimens must be collected using the G.I. Preservative. No other specimens are acceptable.
Rejection Criteria:
Gross hemolysis/lipemia/icteric
Special Specimen Handling and Shipping Instructions
Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.
Shipping Instructions:
Ship specimens frozen in dry ice.
Research & Scientific References
1. A Christ, B Werth, and P Hildebrand. Human Secretin: Biologic Effects and Plasma Kinetics in Humans. Gastroenterology 94: 311, 1988.
2. N Yanaihara, M Sakagami, H Sato, K Yamamoto, T Hashimoto, C Yanaihara, Z Ito, K Yamaguchi, and K Abe. Immunological Aspects of Secretin, Substance P and VIP. Gastroenterology 72: 803, 1977.