Abstract

Absence of gastric acid secretion (anacidity, pH of gastric juice 7 or over) or abnormally low gastric acid secretion (achlorhydria, pH of gastric juice between 3. 6 and 7, depending on the definition) is evidence of the atrophy of gastric mucosa which is always present in adults with pernicious anaemia, and often accompanies chronic hypochromic anaemia, rheumatoid disease, myxoedema, diabetes mellitus, aplastic anaemia, steatorrhoea, and gastric carcinoma; it also occurs in relatives of patients with pernicious anaemia. The only indication for the use of tubeless tests is to demonstrate gastric acid secretion, thus excluding the diagnosis of pernicious anaemia in an anaemic adult. The tests can reliably show that acid is present, but they cannot show conclusively that acid is absent: false negative results are not uncommon. ^1–3 For this reason some consultants doubt whether these tests are worth using.