Diagnostic significance of antibody to intrinsic factor.

Abstract

A circulating substance present in patients with pernicious anaemia and inhibiting the action of intrinsic factor was first demonstrated independently by Schwartz (1958) and Taylor (1959). Subsequent work has confirmed that this substance has the characteristics of an antibody (Abels et al., 1963a ; Ardeman and Chanarin, 1963). Its action is thought to be specifically directed against human intrinsic factor (Ramsay and Herbert, 1965), and it is thus an autoantibody, though cross-reactions with hog intrinsic factor do occur with certain techniques (Schwartz, 1958 ; Taylor and Morton, 1959 ; Lowenstein et al., 1961 ; Gullberg and Kistner, 1963). Using a charcoal absorption technique, Ardeman and Chanarin (1963) detected antibody to intrinsic factor in 57% of patients with pernicious anaemia. Other methods, such as starch-gel electro phoresis (Jeffries et al., 1962), dialysis (Abels et al., 1963b ; Ramsey and Herbert 1965), and tests in vivo (Schwartz, 1958 ; Taylor, 1959), yield a lower proportion of positive results. Antibody to intrinsic factor has not been found in healthy control subjects (Ardeman and Chanarin, 1963 ; te Velde et al., 1964 ; Ramsey and Herbert, 1965). However, apart from its well-documented association with pernicious anaemia of the adult type, the antibody has also been found in those cases of juvenile pernicious anaemia in which histamine-fast achlorhydria and atrophie changes in the gastric mucosa are encountered (Herbert et al., 1964 ; Mclntyre et al., 1965). The antibody has not been demonstrated in those patients with juvenile pernicious anaemia who have a selective lack of intrinsic factor secretion and in whom the secretion of acid and the histology of the stomach are both normal (Mclntyre et al., 1965). The presence of antibody to intrinsic factor in 6 to 7% of patients with Graves's disease (Doniach and Roitt, 1964) emphasizes the close relationship between thyroid disease and pernicious anaemia.