Serum antibodies to gliadin and small-intestinal morphology in dermatitis herpetiformis. A controlled clinical study of the effect of treatment with a gluten-free diet.

Serum gliadin antibodies of the IgA and IgG classes were determined by the diffusion-in-gel enzyme-linked immunosorbent assay in 41 patients with dermatitis herpetiformis before treatment with a gluten-free diet. Increased gliadin antibody levels were found more frequently in patients with subtotal villous atrophy (9 out of 17 patients, or 53%; p less than 0.05) than in patients with partial villous atrophy (2 out of 13 patients, or 15%) or normal villous appearance (2 out of 10 patients, or 20%). The gliadin antibody levels were negatively correlated with the urinary xylose excretion (r = -0.40, p less than 0.02 for the IgA class and r = -0.64, p less than 0.001 for the IgG class). Intestinal morphology improved and mean gliadin antibody levels of the IgA and IgG classes decreased during treatment with a gluten-free diet for 16-36 months (mean, 20 months) (p less than 0.005, n = 26), whereas no significant changes of the gliadin antibody levels or the small-intestinal morphology were observed in the other 15 patients, who continued on a non-restricted diet for 17-35 months (mean, 20 months). Thus, gliadin antibody levels in sera from patients with dermatitis herpetiformis seem to be correlated with the severity of the intestinal disease. However, all patients with villous atrophy are not detected by determination of serum gliadin antibodies.