Standardised approach to gluten challenge in diagnosing childhood coeliac disease.

Thirty-five children, in whom coeliac disease had been diagnosed on inadequate grounds and who had been on a gluten-free diet for one to 10 years, were challenged with gluten in accordance with a standardised procedure. All children were admitted to hospital for 48 hours for general assessment, two one-hour blood xylose tests, and the introduction of gluten. Thirty children underwent a pre-challenge peroral jejunal mucosal biopsy; the specimens were either normal or showed slight non-specific abnormalities. Gluten powder 20 g/day was given in addition to an otherwise gluten-free diet. The children were reassessed as outpatients every two weeks, when a one-hour blood xylose test was performed. Repeat biopsy was performed when xylose absorption fell or after three months. Seventeen children had abnormal post-challenge biopsy appearances compatible with coeliac disease in relapse; 14 of these children completed their challenge within eight weeks. Seventeen children had completely normal biopsy appearances at the end of three months and were returned to a normal diet. One to two years later eight underwent repeat biopsies, which showed nothing abnormal. In only one child, the oldest in the series, were the histological findings equivocal. In the 17 children in whom coeliac disease was confirmed the duration of gluten challenge was not related to age, duration of gluten-free diet, histological findings on the pre-challenge biopsy, or HLA status.