A Distinct Lymphocytic Colitis With Epithelial Damage In Autistic
Children Researchers have confirmed a distinct lymphocytic colitis in autistic
spectrum disorders in which the epithelium appears particularly affected,
and have reported their findings in March's Journal of Pediatrics
A team from the Royal Free and University College School of Medicine
and St Mark's Hospital, London, England investigated the characteristics of
colitis with ileal lymphoid nodular hyperplasia (LNH) in children, and
determined whether LNH was specific for autism.
Ileo-colonoscopy was performed in 21 consecutively evaluated children
with autistic spectrum disorders and bowel symptoms.
Blinded comparison was made with 8 children with histologically normal
ileum and colon, 10 developmentally-normal children with ileal LNH, 15 with
Crohn's disease, and 14 with ulcerative colitis.
The researchers performed immunohistochemistry for cell lineage and
functional markers, and histochemistry for glycosaminoglycans and basement
membrane thickness.
Histology demonstrated lymphocytic colitis in the autistic children,
less severe than classical inflammatory bowel disease. However, basement
membrane thickness and mucosal cell density were significantly increased
above those of all other groups, including patients with inflammatory bowel
disease.
CD8+density and intraepithelial lymphocyte numbers were higher than
those in the Crohn's disease, LNH, and normal control groups; and CD3 and
plasma cell density and crypt proliferation were higher than those in normal
and LNH control groups.
Epithelial, but not lamina propria, glycosaminoglycans were disrupted.
However, the epithelium was HLA-DR-, suggesting a predominantly TH2
response.
Dr Simon Murch said on behalf of the group, "Immunohistochemistry
confirms a distinct lymphocytic colitis in autistic spectrum disorders, in
which the epithelium appears particularly affected. This is consistent with
increasing evidence for gut epithelial dysfunction in autism."
In an accompanying Editorial Perspective, William F. Balistreri
comments, "This seems to point to gut epithelial dysfunction leading to
altered permeability and subsequent entry of central nervous system-altering
substances.
"It follows that treatment of the gut disease may affect the CNS
disease."
