Does gluten sensitivity play a role in Alzheimer's disease ?

Celiac disease (CD) is an autoimmune disorder and transglutaminase is the autoantigen recognized in gut endomysium. CD can involve organs other than intestine. The aetiology of a large proportion of Alzheimer's Disease(AD) cases is still unexplained . Even if an association between CD and AD has never been found, tissue transglutaminase (tTG) may be involved in the pathogenesis of AD by facilitating deposition of Aβ42 and formation of hyperphosphorylated protein tau. Aim of the study was to search for the relationship of AD with CD. We studied 107 patients with “probable Alzheimer´s Disease” according to NINCDS-ADRDA criteria; sera were collected to determine IgA and IgG-tTG antibodies by a home made ELISA and IgA-antiendomysium antibodies (EMA) by indirect immunofluorescence. Six patients were positive for tTG (2 IgA-tTG, 3 IgG-tTG, 1 both IgA and IgG-tTG) but negative for EMA. 3/6 underwent identification of aplotype HLA: one patient only was DQ2. No patient accepted to undergo duodenal biopsy. The prevalence of tTG positive patients in our study population (6%) is higher compared with that reported in mass screening studies for CD (1%). No patient in our study underwent intestinal biopsy and nobody was EMA positive, a test that is predictive of villous atrophy. However, we suggest to address the hypothesis that patients with AD might be similar to those reported by Hadjivassiliou with ataxia of unknown cause who had gluten sensitivity and response to a gluten free diet even in the absence of villous atrophy.