Correct interpretation of physical examination indicators: pepsinogen and serum gastrin 17

2022-06-03 0 By

With the increasing attention paid to pepsinogen ⅰ (PG ⅰ), ⅱ (PG ⅱ) and gastrin-17 (G-17), these indexes have become indispensable items in physical examination.It is used to screen patients with chronic atrophic gastritis and those at high risk of gastric cancer in asymptomatic populations.But for these 2 categories, 3 indicators, we are still very strange, do not know the real meaning of their representatives, here to give a detailed talk, so that you understand to reduce unnecessary panic.Physical examination indicators: pepsinogen is the precursor of pepsin, which is divided into two subgroups according to its biochemical properties and immunogenicity. Components 1-5 have the same immunogenicity, called pepsinogen I, which is mainly secreted by the main cell and mucinous neck cells of the gastric fundus gland.Components 6 and 7, known as pepsinogen II, are secreted by the main cells of the fundus gland and mucinous neck cells, as well as the mucinous neck cells of the pyloric glands of the cardiac gland and gastric antrum, and the upper duodenum.Early superficial gastric mucosal inflammation can stimulate the main cells to secrete PG, gastric acid and gastrin. Therefore, in the early stage of gastric mucosal inflammation, PG ⅰ will increase, and PG ⅱ may also increase, but the PG ⅰ /PG ⅱ ratio will not decrease or even increase.Then, slowly with the progressive development of inflammation, gastric mucosa atrophy, especially gastric fundus and gastric body mucosa atrophy, so that the number of recipient cells decreased;At the same time, mucosal inflammation itself can also cause damage to the master cells, further damaging the secretion function of the host cells, so PG ⅰ will decrease at this time.In addition, gastric mucosa atrophy can also cause the proliferation of gastric antrum cells and the increase of PG ⅱ secretion, so the PG ⅰ /PG ⅱ ratio will decrease.The more severe gastric atrophy, the more severe the decrease of PG ⅰ /PG ⅱ ratio.Physical Indicators: Serum gastrin 17(G17) Gastrin is an important gastrointestinal hormone secreted mainly by G cells.G cells are typical open cells, most of which are in gastric antrum, followed by gastric fundus, duodenum and jejunum.Gastrin 17 is the most important substance in human body (about 90%).Gastrin 17 is one of the indicators reflecting the structure and functional status of gastric mucosa, but serum G17 is affected by H. pylori infection, gender, age, lesion site, PPI preparation, renal function, diabetes, pernicious anemia and other factors and diseases, so the clinical significance of the indicator should be fully understood by comprehensive consideration and evaluation.(1) Reasons for the increase of G-17 level: gastric mucosa atrophy, gastric acid secretion and negative feedback inhibition of G cells in gastric antrum are reduced, resulting in increased secretion of gastrin by G cells and increased G-17 level.Elevated LEVELS of G-17 were also seen in patients with long-term use of acid-suppressing drugs such as proton pump inhibitors (PPI) and in patients with gastrinoma.(2) The reasons for the decrease of G-17 level: gastric antrum mucosa atrophy and g-17 level decreased;Gastric mucosa destruction caused by gastric antrum ulcer and gastric antrum surgery can reduce the number of G cells in gastric antrum and the secretion of G-17, resulting in the decrease of blood G-17 level.At present, PG ⅰ, PG ⅰ /PG ⅱ ratio and G-17 level only reflect the degree of gastric mucosa atrophy, and their value in the diagnosis of gastric cancer has not been confirmed.Most of the changes in serum PG ⅰ, PG ⅰ /PG ⅱ ratio and G-17 level are due to gastric mucosa inflammation rather than cancer, so do not be alarmed.If you find abnormal indicators in your physical examination, please go to the hospital in time, and professional doctors will interpret the results for you. If necessary, helicobacter pylori infection, gastroscopy and other examinations will be detected to evaluate whether there is gastric mucosal atrophy and its severity, and tissues will be obtained through biopsy for pathological diagnosis, which is the “gold standard”!(Pictures from Internet)