Pepsinogen I (PG I)

Clinical Significance:
The Pepsinogens are gastric acid protease zymogens.  They are divided into two distinct immunochemical groups:  Pepsinogen I and II.  Pepsinogen I is produced primarily in the Oxyntic gland mucosa of the stomach.  It is secreted mainly into the gastric lumen and into circulation.  Pepsinogen I has little or no biological activity but in acid is converted to the active enzyme Pepsin which exhibits proteolytic actions.  Pepsinogen I is cleared by the kidney and secreted into the urine.  Patients with pernicious anemia and gastrectomized patients have low to non-detectable levels of Pepsinogen I.  Pepsinogen I levels are slightly elevated in gastric ulcer, higher in gastroduodenal ulcer and significantly elevated in duodenal ulcer.  Patients with Zollinger-Ellison’s syndrome exhibit greatly elevated levels.  Pepsinogen I has been shown to correlate with presence of genetic duodenal ulcer, and has been used as a subclinical marker of increased risk for stomach cancer.

Reference Range:
28 – 100 ng/ml

Procedure:
Pepsinogen I is measured by direct EIA/ELISA.

Patient Preparation:
Patient should be fasting 10 – 12 hours prior to collection of specimen.  Antacids or other medications affecting stomach acidity or gastrointestinal motility should be discontinued, if possible, for at least 48 hours prior to collection.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Freeze specimens immediately after separation.  Minimum specimen size is 1 ml.

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.

References:
1. M Plebani, F DiMauro, PL Dal Santo. D Faggian, B Germana, and F Vianello.  Measurement of Pepsinogen Group I in Endoscopic Gastroduodenal Biopsies.  Clinical Chemistry 36:  682-684, 1990.

2. IM Samloff and WM Liebmann. EIA/ELISA of Group I Pepsinogens in Serum.  Gastroenterology 66:  494, 1974.