Gluten sensitivity in a subset of children with insulin dependent diabetes mellitus.

Objectives: The association between celiac disease and insulin dependent diabetes mellitus (IDDM) is well established. Rectal gluten challenge has been used in patients with celiac disease and in first degree relatives as a tool to assess the mucosal immune response to gluten. The aim of this study was to assess the mucosal immune response to gluten in IDDM children by rectal gluten challenge.

Methods: Rectal biopsy specimens were obtained from 19 children with IDDM before and 6 h after rectal challenge with 2 g of a peptic tryptic digest of gliadin. A total of 16 treated celiac patients and 10 control subjects were also investigated. Epithelium and lamina propria CD3(+) and gamma delta(+) lymphocytes were counted with reference to a standard reference area of muscularis mucosae (10(4) microm(2)).

Results: After a local instillation of gliadin, a significant (>mean + 1 SD) percentage increment of lamina propria and epithelium CD3(+) and of lamina propria and epithelium gamma delta(+) lymphocytes was observed in five IDDM children, as compared to 11 and 13 celiac patients and one and two controls, respectively. A discriminant analysis allowed correct classification of 100% of patients with celiac disease and controls. The same analysis classified four of 19 IDDM children in the group of celiac patients. The positivity was associated with normal serology (antigliadin antibody, antiendomysial antibody, and antitissue transglutaminase antibodies) and a morphologically normal jejunal mucosa. All four patients had HLA-DQ alleles associated with celiac disease.

Conclusions: Approximately 20% of IDDM children react to rectal instillation of gliadin. Long term follow-up is necessary to establish whether these subjects are at increased risk for developing celiac disease.