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The American Journal of Clinical... Jul 2015We re-evaluated the old hypothesis that gastritis-induced achlorhydria is a cause of iron deficiency anemia (IDA) in humans. First, we analyzed the currently available... (Review)
Review
We re-evaluated the old hypothesis that gastritis-induced achlorhydria is a cause of iron deficiency anemia (IDA) in humans. First, we analyzed the currently available research on the association between achlorhydria and IDA. When gastric acid secretion was measured after maximal stimulation, the frequency of achlorhydria (or severe hypochlorhydria) was 44% in patients with idiopathic IDA and 1.8% in healthy controls. In some patients with pernicious anemia, presumed achlorhydria preceded the development of IDA in time. However, we found no credible evidence that IDA caused gastritis or that IDA preceded the development of achlorhydria. Thus, correlational results favor achlorhydria as the causal factor in the association between achlorhydria and IDA. Second, we sought to determine whether gastritis and achlorhydria cause negative iron balance. When biosynthetic methods were used to isotopically label iron in food, achlorhydric patients were found to have severe malabsorption of nonheme iron, which persisted after the development of IDA. In 1 study, achlorhydria reduced the normal increase in heme-iron absorption from hemoglobin in response to iron deficiency. After an injection of isotopic iron into normal men, the physiologic loss of iron from the body was found to be 1 mg/d. Patients with chronic gastritis had excess fecal loss of isotopically tagged plasma iron. Calculations based on these results indicate that the absorption of iron from a typical Western diet by achlorhydric patients would be less than physiologic iron losses, creating a negative iron balance that could not be overcome by the adaptive increase in duodenal iron absorptive capacity that occurs in response to iron deficiency. The combination of results from these correlational and pathophysiologic studies supports the hypothesis that gastritis-induced achlorhydria can be an independent cause of IDA.
Topics: Achlorhydria; Anemia, Iron-Deficiency; Duodenum; Gastritis; Hemoglobins; Humans; Iron, Dietary
PubMed: 25994564
DOI: 10.3945/ajcn.114.097394 -
Scandinavian Journal of Clinical and... 2006Gastrin and gastrin receptor-deficient mice have been used for genetic dissection of the role of gastrins in maintaining gastric homeostasis and control of acid... (Review)
Review
Gastrin and gastrin receptor-deficient mice have been used for genetic dissection of the role of gastrins in maintaining gastric homeostasis and control of acid secretion. The gastrin knockout mice are achlorhydric due to inactivation of the ECL and parietal cells. Moreover, this achlorhydria is associated with intestinal metaplasia and bacterial overgrowth, which ultimately leads to the development of gastric tumours. The association between progastrin, progastrin-derived processing intermediates and colorectal carcinogenesis has also been examined through genetic or chemical cancer induction in several mouse models, although the clinical relevance of these studies remains unproven. While others have focused on models of increased gastrin production, the present review describes the lessons learned from gastrin-deficient mice. Study of these mice helps our understanding of how dysregulation of gastrin secretion may be implicated in human disease.
Topics: Achlorhydria; Animals; Gastric Acid; Gastric Mucosa; Gastrins; Gene Expression Regulation; Intestinal Diseases; Metaplasia; Mice; Mice, Knockout; Models, Biological; Receptor, Cholecystokinin B; Stomach Neoplasms
PubMed: 17101553
DOI: 10.1080/00365510600873894 -
Gut Apr 1987
Review
Topics: Achlorhydria; Animals; Gastric Mucosa; Gastrins; Humans; Rats; Stomach Neoplasms
PubMed: 3556339
DOI: 10.1136/gut.28.4.488 -
Gastroenterologie Clinique Et Biologique Jan 1999
Review
Topics: Achlorhydria; Anti-Ulcer Agents; Gastritis; Gastroesophageal Reflux; Humans; Infections; Stomach Diseases; Stomach Neoplasms
PubMed: 10078439
DOI: No ID Found -
The New England Journal of Medicine Dec 1971
Topics: Achlorhydria; Histamine; Humans; Stomach Ulcer
PubMed: 5122900
DOI: 10.1056/NEJM197112232852615 -
European Journal of Clinical Nutrition Dec 1989Zinc absorption from 40 mumol of zinc in a water solution and from a test meal containing 22 mumol of zinc was studied in 8 patients with achlorhydria (no basal acid... (Clinical Trial)
Clinical Trial
Zinc absorption from 40 mumol of zinc in a water solution and from a test meal containing 22 mumol of zinc was studied in 8 patients with achlorhydria (no basal acid secretion and no secretion after pentagastrin stimulation). The test dose and the meal was labelled with 0.1 MBq of 65Zn and absorption was determined from measurement of the whole-body retention of the isotope. Zinc absorption was 68 +/- 16 per cent (mean +/- s.d.) from the water solution and 33 +/- 10 per cent from the test meal. The results did not differ from absorption in control subjects and indicate that achlorhydria per se does not affect zinc absorption.
Topics: Achlorhydria; Adult; Clinical Trials as Topic; Female; Gastric Acid; Humans; Intestinal Absorption; Male; Middle Aged; Zinc
PubMed: 2697554
DOI: No ID Found -
Lancet (London, England) Dec 1991The association between achlorhydria and gastric carcinogenesis can be explained by a simple hypothesis based on the known cytological properties of neoplastic cells and...
The association between achlorhydria and gastric carcinogenesis can be explained by a simple hypothesis based on the known cytological properties of neoplastic cells and the physiology of the stomach. Normal gastric secretions might ensure the rapid elimination of carcinomatous cells. Achlorhydria could be an important permissive factor in the development of gastric carcinoma.
Topics: Achlorhydria; Gastric Mucosa; Humans; Neoplastic Cells, Circulating; Nitroso Compounds; Stomach Neoplasms
PubMed: 1683930
DOI: 10.1016/0140-6736(91)92312-p -
The Medical Journal of Australia Oct 1961
Topics: Achlorhydria; Follow-Up Studies; Gastric Juice
PubMed: 13915460
DOI: No ID Found -
The American Journal of Clinical... Dec 2015
Topics: Achlorhydria; Anemia, Iron-Deficiency; Humans
PubMed: 26628570
DOI: 10.3945/ajcn.115.120550 -
The Medical Annals of the District of... Oct 1971
Topics: Achlorhydria; Adult; Alcoholism; Atrophy; Chronic Disease; Gastritis; Humans; Malabsorption Syndromes; Middle Aged; Postgastrectomy Syndromes
PubMed: 5287414
DOI: No ID Found