Is gluten challenge really necessary for the diagnosis of coeliac disease in children younger than age 2 years?

Clinical practice : coeliac disease

Coeliac disease (CD) is an immune-mediated systemic condition elicited by gluten and related prolamines in genetically predisposed individuals and characterised by gluten-induced symptoms and signs, specific antibodies, a specific human leukocyte antigen (HLA) type and enteropathy. The risk of coeliac disease is increased in first-degree relatives, certain syndromes including Down syndrome and autoimmune disorders. It is thought to occur in 1 in 100-200 individuals, but still only one in four cases is diagnosed. Small-bowel biopsy is no longer deemed necessary in a subgroup of patients, i.e. when all of the following are present: typical symptoms or signs, high titres of and transglutaminase antibodies, endomysial antibodies, and HLA-type DQ2 or DQ8. In all other cases, small-bowel biopsy remains mandatory for a correct diagnosis. Therapy consists of a strictly gluten-free diet. This should result in complete disappearance of symptoms and of serological markers. Adequate follow-up is considered essential.

CONCLUSION

Although small-bowel biopsy may be omitted in a minority of patients, small-bowel biopsy is essential for a correct diagnosis of CD in all other cases. Diagnostic work-up should be completed before treatment with gluten-free diet instituted.

Celiac disease screening assays for children younger than 3 years of age: the performance of three serological tests

BACKGROUND AND AIMS

The optimum serological test for celiac disease (CD) in young children is not known. The objective of our study was to compare the performance of three serological tests (IgA + IgG DGP, IgA TTG, and IgA + IgG EMA) for children younger than 3 years of age.

METHODS

We identified all subjects younger than 3 years of age (n = 6,074) that were tested for CD serology and included those with biopsy data. Patients were classified as group 1 (n = 47): patients with confirmed CD or group 2 (n = 12): patients with normal biopsy findings.

RESULTS

There was statistically significant difference between group 1 and group 2 with regard to number of patients with positive IgA TTG (97.87% vs. 50%, P < 0.001), IgA + IgG DGP (100% vs. 77.78%, P = 0.007), and IgA + IgG EMA (95.65% vs. 9.09%, P < 0.001). There was a significantly positive correlation between Marsh-Oberhuber score on the small duodenal biopsies and all tests. Analysis of sensitivity and specificity showed that manufacturer's levels had high sensitivity for all tests (IgA TTG 97%, IgA + IgG DGP 100%, IgA + IgG EMA 96%), however specificity was low for IgA + IgG DGP (44%) and IgA TTG (50%) but not for IgA + IgG EMA (91%).

CONCLUSIONS

For children younger than 3 years of age, IgA + IgG EMA is highly sensitive and specific. Use of IgA + IgG DGP or IgA TTG as a single serological marker is insufficient for definite diagnosis of CD in this age group. Based on our results, it might be reasonable to postpone the biopsy for asymptomatic children with negative EMA.