Incidence of gastric parietal cell antibody in families of patients with iron deficiency anaemia

There is an association of pernicious anaemia with iron deficiency anaemia (Faber and Gram, 1924). There is also a high incidence (85 per cent) of gastric parietal cell antibody in the sera of patients with pernicious anaemia (Taylor, Roitt, Doniach, Couchman and Shapland, 1962) and a less marked, but significantly increased incidence (33 per cent) in patients with iron deficiency anaemia who have a histamine fast achlorhydria (Dagg, Goldberg, Anderson, Beck and Gray, 1964). Pernicious anaemia has a familial incidence (Askey, 1940; Callender and Denborough, 1957) and there is also an increased frequency of achlorhydria in relatives of patients with pernicious anaemia (Askey, 1940; Neel, 1947). In addition te Velde, Abels, Anders, Arends, Hoedemaeker and Nieweg (1964) have found the gastric parietal cell antibody in 20 per cent of relatives of patients with pernicious anaemia, compared with 6 per cent in a control series. Because of the association of iron deficiency anaemia with pernicious anaemia and the increased incidence of histamine fast achlorhydria and parietal cell antibody in both diseases, the occurrence of the antibody has been assessed in the families of patients with iron deficiency anaemia, histamine fast achlorhydria and gastric parietal cell antibody. In a group of 22 patients with iron deficiency anaemia, histamine fast achlorhydria and gastric parietal cell antibody, Dagg, Goldberg, Gibbs and Anderson (1966) found that seven had a ⁵⁸Co vitamin B₁₂ absorption test (Schilling, 1953) characteristic of pernicious anaemia, and six of these had reduced serum vitamin B₁₂ levels; that is these patients had latent pernicious anaemia. In 10 of the 22 patients the serum vitamin B₁₂ levels and the Schilling test were normal, and in the remaining five patients the serum vitamin B₁₂ was low but the Schilling test was normal. Since it appeared possible that the familial incidence of gastric parietal cell antibody would be higher in relatives of the patients with latent pernicious anaemia than in relatives of those without latent pernicious anaemia, 11 families from these 22 patients were investigated, six of which had propositi with latent pernicious anaemia and five of which had propositi without latent pernicious anaemia (Table I). The relatives of the remaining 11 patients were unwilling to co-operate in these investigations.