Infant Nutrition and Risk of Celiac Disease

From weaning to age 12 months the clinical data, the adherence to the dietary protocol and the amount of intervention baby-food ingested will be checked every month. Following investigations will be performed at the time of recruitment, at time of weaning and at 12, 18, 24, 30,36, 42, 48, 54 and 60 months by taking a sample of blood (maximum 4 ml) from infants (a) quick test for IgA anti-tTG abs determination (few drops); (b) conventional ELISA for serum IgA and IgG anti-tTG determination (0.4 ml);(c) serum zonulin determination (0.1 ml); (e) serum sample for T1D-related autoantibodies (0.25 ml); (f) serum sample to be stocked in the sera bank (0.25 ml); (g) whole blood sample in EDTA for validation of the quick tests (0.5 ml). All the sera samples will be frozen, stored at -20 °C and sent (boxed in dry ice) in blocks to the centre responsible for the determinations every 2 months. Cases positive for the quick-test for anti-tTG the serum sample will be frozen and immediately shipped for confirmatory determination.

If infants develop symptoms during the intervention period (6 to 12 months) the group to which infant belongs will be decoded. Infants belonging to group A (on a gluten-containing diet) presenting symptoms suggestive of CD will undergo a complete diagnostic work-up for CD. These events will be reported in a form. After age 1 year, infants developing symptoms suggestive of active CD (chronic diarrhea, failure to thrive, etc) in-between the scheduled visits will undergo a supplementary serological investigation. A small intestinal biopsy will be recommended in cases showing either serum anti-tTG abs higher than the cut-off or IgG-AGA higher than cut-off in infants with selective IgA deficiency. (Standard medical care and not part of research).

The evolution of the composition of the intestinal microbiota will be evaluated in both groups at 7d, 30d, 4-6 months (prior to weaning), 12,18,24,30,36, 42, 48, 54 and 60 months. The bacterial composition of stool will also be analyzed in a sub-sample of children developing active CD and in non-CD controls. All patients who develop CD will continue in the study.

Definitions:

Active CD: Children showing positive serology and signs of immune-mediated damage of the small intestinal mucosa on biopsy (ranging from isolated increase of intraepithelial lymphocytes to villous atrophy with crypt hypertrophy.)

CD serological autoimmunity positive: Children positive for IgA anti-tTG abs on two consecutive occasions.

Disruption of the small intestinal barrier: Children with an increased ratio of serum lactulose/mannitol with or without increased levels of serum zonulin.