Magnesium hydrogen breath test using end expiratory sampling to assess achlorhydria in pernicious anaemia patients

Review article: methods of measuring gastric acid secretion

BACKGROUND

Gastric acid has an important pathophysiological role in human beings. Numerous methods have been evaluated over the years in an attempt to measure gastric acid and stomach acidity, to study the role of gastric acid in gastrointestinal diseases in humans and to evaluate the effects of acid suppressing drugs.

AIM

To review methods that have been used to measure gastric acid and gastric acidity.

METHODS

Searches of the electronic databases PUBMED, MEDLINE and EMBASE, were performed with articles restricted to English language and human subjects. References were also identified from the bibliographies of selected articles.

RESULTS

Methods for measuring gastric acid include both invasive and non-invasive techniques. Invasive tests include the conventional gastric acid aspiration tests, gastric pH measurement techniques and endoscopic methods. Non-invasive methods use urinary analysis, breath analysis, serum pepsinogens assay, scintigraphic techniques, impedence tomography and alkaline tide for measurement of gastric acid.

CONCLUSIONS

Several methods of measuring gastric acid exist. Invasive tube tests are uncomfortable and time consuming, whereas most of the non-invasive methods are at best semiquantitative and useful in detecting low or absent acid secretion. Further attempts to explore new methods for measuring gastric acid are therefore warranted.

Detection of early abnormalities in gastric function in first-degree relatives of patients with pernicious anemia

BACKGROUND

Pernicious anemia (PA), as many other autoimmune disorders, has a trend to appear in other members of the family of the affected patients. Although this fact has been recognized since some decades ago, less is known about the frequency with which the abnormalities detected in the patients appear also in their relatives, the correlations that exist among these abnormalities and to what extent these markers of the disease relate to serum cobalamin concentration.

SUBJECTS AND RESULTS

For these reasons we studied the values of some markers of PA in a group of 79 first-degree relatives and we detected that the most frequent abnormalities are a decrease in serum pepsinogen I (22.7% of cases), an increase in serum gastrin (16.5% of cases) and in parietal cell antibody at a titer >or=40 (23.4% of cases). From a functional point of view, a decrease in hydrogen excretion in a magnesium breath test, indicative of achlorhydria, is also frequent (29.1%). The fall in cobalamin concentration runs in parallel with these abnormalities. The concentration of this vitamin was below normal levels in as much as 15.2% of cases.

CONCLUSION

These findings emphasize the need for searching for the presence of occult or latent PA in relatives of patients with this diagnosis, not only to prevent the development of anemia but also to avoid other undesirable consequences of cobalamin deficiency.