Serological markers identify histologically latent coeliac disease among first-degree relatives

Serological markers detect asymptomatic coeliac disease among first-degree relatives of patients with sprue. However, some relatives with coeliac disease-related antibodies have 'normal' jejunal mucosa by conventional histology. Whether these serological abnormalities represent false-positives or are consequences of gluten sensitivity is not known. Our aim was to evaluate, through quantitative histology, intestinal biopsies of asymptomatic relatives of probands seeking abnormalities consistent with latent coeliac disease.

Fifty-nine intestinal biopsies obtained from asymptomatic relatives were evaluated; 40 samples were suitable for histological quantification. Seven samples showed severe mucosal atrophy (coeliac disease) and 33 were considered as 'normals'. In the 'normal' group, nine samples were obtained from patients with one or more positive serological tests and 24 from those with negative tests. Morphometry was compared for samples obtained from healthy control individuals (n = 10) and for those from coeliac patients (n = 7).

Serological tests used were: antigliadin antibodies type immunoglobulin (Ig)A and IgG (enzyme-linked immunosorbent assay), antirrecticulin antibody (immuno-fluorescence) and endomysial antibody (immunofluorescence). Biopsy samples were obtained with endoscopic forceps from the distal duodenum (second portion). Quantitative histology of duodenal biopsies was performed with a computerized image analysis system.

Relatives with positive serology showed shorter villi (P < 0.05) and higher number (P < 0.01) and numerical density (P < 0.01) of intraepithelial lymphocytes in crypts than healthy controls. Numerical density of intraepithelial lymphocytes in crypts in antibody-positive patients was significantly higher than that observed in relatives with negative serology (P < 0.03). Four of nine (44%) relatives with positive serology had a number of intraepithelial lymphocytes in crypts within the range of coeliac disease patients. However, only one patient with negative serology (4%) was in this range.

Our study shows quantitative histological evidence that relatives of probands with positive coeliac disease-related serology are not false-positives, and that they should be considered as individuals with latent coeliac sprue.