This study determined the location and tissue

Serum tumour necrosis factor a (TNFa) concentrations were measured by enzyme linked immunoadsorbent assay in 31 normal children and during 65 episodes of clinical remission and 54 episodes of relapse in 92 children with

SUMMARY Proximal small intestinal and colonoscopic mucosal biopsies from two children with the intractable diarrhoea of infancy syndrome were examined by electron microscopy. Microvillous involutions were found in the small and large bowel of both patients. We suggest that this is a specific diagnostic finding for congenital microvillous atrophy, a distinct disorder within the intractable diarrhoea syndrome which has an extremely poor prognosis.

(non-T cell) population is reduced to 1*4% of the CD7+ cells. In contrast, in patients with villous atrophy of uncertain aetiology, all CD4-, CD8-lymphocyte subsets are decreased compared with normal biopsies. Finally, in enteropathy associated T cell lymphoma (malignant histiocytosis of the intestine) in which the 'uninvolved mucosa' is histologically similar to untreated coeliac disease, the changes in the intraepithelial T cell sub-sets are indistinguishable from those in coeliac disease, suggesting that the lymphoma is a complication of coeliac disease.The intraepithelial lymphoid population, a compartment of gut associated lymphoid tissue, is distinct phenotypically and functionally from lymphoid cells in other organs. Studies of human intraepithelial lymphocytes in tissue sections and in preparations of isolated cells have shown them to be predominantly CD3 positive T cells, most of which also express CD8. A large proportion of intraepithelial T cells do not express CD5, which is a pan T cell marker in other tissues.'2 Approximately 20-35% of human intraepithelial lymphocytes contain cytoplasmic

despite the use of immunosuppressive drugs. Organ specific and non-organ specific autoimmune diseases or corresponding autoantibodies or both were often found in children with enterocyte autoantibodies and their family. These data show the existence of an autoimmune vanant of protracted diarrhoea of infancy, despite the rare occurrence of autoimmune diseases in childhood.

The IGF system, as shown by serum IGF-I and IGFBP-3, is responsive to therapeutic intervention in active Crohn's disease. It is likely that a combination of decreased inflammatory activity and improved nutrition contributes to these changes.

A strong HLA association is seen in coeliac disease [specifically to the DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account for the increased risk seen in relatives of affected cases. One or more genes at HLA-unlinked loci also predispose to coeliac disease and are probably stronger determinants of disease susceptibility than HLA. A recent study has proposed a number of candidate regions on chromosomes 6p23 (distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3, 19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked susceptibility gene. We have examined these regions in 28 coeliac disease families by linkage analysis. There was excess sharing of chromosome 6p markers, but no support for a predisposition locus telomeric to HLA. No significant evidence in favour of linkage to coeliac disease was obtained for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or 22cen. There was, however, excess sharing close to D15S642. The maximum non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for linkage of coeliac disease to chromosome 15q26 is not strong, the well established association between coeliac disease and insulin dependent diabetes mellitus, together with the mapping of an IDDM susceptibility locus (IDDM3) to chromosome 15q26, provide indirect support for this as a candidate locus conferring susceptibility to coeliac disease in some families.

SUMMARY Over a 10 year period a total of 102 teenage patients with coeliac disease were assessed on transfer from paediatric hospitals to an adult clinic. Fifty seven patients said they were on a strict gluten free diet; 36 were semistrict, and nine admitted to eating a normal diet. Jejunal mucosal abnormalities, however, suggested that many patients on the 'strict' diet were actually consuming gluten. All patients were well with biochemical parameters within the normal range. Height percentiles were not significantly different from the normal population but patients, as a group, were significantly lighter.