Persistently positive gliadin antibodies without transglutaminase antibodies in the elderly: gluten intolerance beyond coeliac disease.

Background: The specificity of the conventional gliadin antibody test is considered low.

Aims: We explored whether gliadin antibody(AGA)-positivity without tissue transglutaminase antibodies (tTGA) is persistent in the elderly population and whether such positivity indicates overt or potential coeliac disease in genetically predisposed individuals.

Methods: AGA and tissue transglutaminase antibody were measured in 2089 elderly individuals twice with a three-year interval. AGA-positive but tissue transglutaminase antibody-negative subjects with coeliac-type human leucocyte antigen (HLA) were examined and underwent gastroduodenal endoscopy (cases). Small-bowel mucosal villous morphology and densities of CD3+ and γδ+ intraepithelial lymphocytes and the occurrence of tissue transglutaminase-specific IgA deposits were analysed. Randomly selected persistently AGA-negative age- and sex-matched subjects served as controls.

Results: AGA-positivity was persistent in 81% of those initially positive. Amongst the 49 clinically studied and 36 endoscopied cases only one (2.8%) had coeliac disease. Many (54%) showed signs of inflammation in the biopsy, without villous atrophy. Coeliac-type HLA was not over-represented in the persistently AGA-positive compared to the general population. Persistently AGA-positive coeliac-type HLA-positive subjects had more gastrointestinal symptoms than AGA-negative controls.

Conclusions: AGA-positivity is often persistent. Overt coeliac disease is seldom found behind persistent AGA-positivity, but this characteristic is associated with mucosal inflammation and gastrointestinal symptoms at least in HLA-positive individuals.