gastrin-17 and Achlorhydria

Atrophic gastritis (AG) results most often from Helicobacter pylori (H. pylori) infection. AG is the most important single risk condition for gastric cancer that often leads to an acid-free or hypochlorhydric stomach. In the present paper, we suggest a rationale for noninvasive screening of AG with stomach-specific biomarkers.. The paper summarizes a set of data on application of the biomarkers and describes how the test results could be interpreted in practice.. In AG of the gastric corpus and fundus, the plasma levels of pepsinogen I and/or the pepsinogen I/pepsinogen II ratio are always low. The fasting level of gastrin-17 is high in AG limited to the corpus and fundus, but low or non-elevated if the AG occurs in both antrum and corpus. A low fasting level of G-17 is a sign of antral AG or indicates high intragastric acidity. Differentiation between antral AG and high intragastric acidity can be done by assaying the plasma G-17 before and after protein stimulation, or before and after administration of the proton pump inhibitors (PPI). Amidated G-17 will rise if the antral mucosa is normal in structure. H. pylori antibodies are a reliable indicator of helicobacter infection, even in patients with AG and hypochlorhydria.. Stomach-specific biomarkers provide information about the stomach health and about the function of stomach mucosa and are a noninvasive tool for diagnosis and screening of AG and acid-free stomach.

Topics: Achlorhydria; Antibodies, Bacterial; Biomarkers; Gastric Mucosa; Gastrins; Gastritis, Atrophic; Helicobacter Infections; Helicobacter pylori; Humans; Mass Screening; Pepsinogen A; Pepsinogen C; Stomach Neoplasms; Vitamin B 12

Methods for the measure of gastric acid secretion include invasive and non-invasive tests. The gold-standard to measure the acid output is the collection of gastric after in basal condition (Basal Acid Output, B.A.O.) and after an i.m. injection of pentagastrin (Maximal Acid Output, M.A.O.). However, direct measurement of gastric acid production is out of order in clinical practice, but many GI symptoms are claimed to be related with acid disorders and empirically cured. Hypochlorhydria is associated with precancerous conditions such as chronic atrophic gastritis (CAG). Acid measurement with non-invasive methods (pepsinogens) is supported by international guidelines.

Topics: Achlorhydria; Biomarkers; Gastric Acid; Gastric Acidity Determination; Gastrins; Gastritis, Atrophic; Humans; Pentagastrin; Pepsinogens; Peptic Ulcer; Precancerous Conditions

In 68 patients with chronic renal failure (CRF), 15 patients with duodenal ulcer and 15 normal subjects, basal plasma gastrin levels and basal and stimulated gastric acid secretion were measured. Two antisera were used: antiserum R2702 with specificity for human G34 and its N-terminal fragments [G34] and antiserum 2604 with specificity for the four main components of gastrin (total gastrin). Basal gastrin concentrations of both total gastrin and G34-like immunoreactivity (G34LI) were significantly higher in the CRF patients than in the other two groups, irrespective of dialysis. Total gastrin levels were not correlated with serum creatinine levels. Total gastrin levels were significantly decreased during hemodialysis, but G34LI levels showed no significant change. A small amount of total gastrin was detected in the dialysate by antiserum 2604. As to the postprandial gastrin release, in the first 30 min, the pattern of response in the patients with CRF was similar to that of the normal subjects, but the peak value was attained later, and the response was more rather prolonged. Gastric analysis showed a low basal acid out put and impaired acid secretion in response to secretagogue. It is concluded that (1) one of the predominant circulating forms of gastrin in CRF is G34LI, and (2) the hypergastrinemia in the CRF patients is probably due to reduced removal of gastrin by kidneys, increased gastrin production by impairment of the negative acid feedback mechanism induced by parietal cell dysfunction or reduced parietal cell sensitivity to gastrin by atrophic gastritis.

Topics: Achlorhydria; Adult; Endoscopy; Female; Food; Gastric Acid; Gastrins; Humans; Kidney Failure, Chronic; Male; Middle Aged; Protein Precursors; Renal Dialysis

We determined total gastrin and pepsinogen I in frozen serum samples from 175 overnight-fasted women 54 years old, and from 81 overnight-fasted women 60 years old, who took part in a population study in 1968-69. We also assayed samples from some of these women, who participated in clinical follow-up studies in 1974-75 and 1980-81: all of the women in the initial group whose serum gastrin concentration exceeded the 85th centile value and, as a reference group, a randomized subsample of women whose initial serum gastrin concentration was less than the 80th centile. Samples with total gastrin concentration greater than 400 ng/L were also assayed for gastrin-17 and gastrin-34. We found that: a pronounced increase of serum gastrin persisted throughout the study period for most of these postmenopausal women, indicating that conversion of type A gastritis (antrum-sparing) to pan-gastritis is uncommon; unexplained high concentrations of pepsinogen I in relation to the reference interval for young and middle-aged adults, as well as in relation to serum gastrin, were common; and the gastrin-17/gastrin-34 ratio is not correlated with the outcome of pronounced hypergastrinemia.

Topics: Achlorhydria; Fasting; Female; Follow-Up Studies; Food; Gastrins; Gastritis; Humans; Longitudinal Studies; Middle Aged; Pepsinogens; Sweden