Celiac disease (CD) is an immune-mediated systemic disease that is elicited by consumption of gluten and related prolamines in genetically susceptible individuals. Not only genetic but also environmental factors play an important role in CD pathogenesis. CD patients have imbalance in the gut microbiota, they have reduced number of Bididobacterium species in feces and biopsies.

Up till now, only effective treatment for CD is life long adherence to gluten free diet. If gluten free diet is not strict that leads over the years to complications of disease, such as autoimmune diseases, psychiatric diseases, osteoporosis etc. That may be caused by continuous recirculation of activated immune cells between the inflamed organ and the periphery. To avoid complications of disease in long term the investigators want to test specific probiotic bacteria from Bifidobacteria genus, that has has been in vitro studies recognized as anti-inflammatory.

Hypothesis

1. Children with celiac disease on gluten free diet have a higher level of pro-inflammatory cytokine (TNF-alpha) and anti-inflammatory cytokine (IL-10) in comparison with healthy controls.
2. 3 months after daily probiotic consumption TNF-alpha level decrease and IL-10 level increase.

In the investigators research will be selected 70 children, age from 2 to 18 years, divided in different groups:

1. Group: 25 children with celiac disease on GFD for at least 3 months and will receive probiotic for 3 months.
2. Group: 25 children with celiac disease on GFD for at least 3 months and will receive placebo for 3 months.
3. Group: 20 healthy children

Inclusion Criteria:

• celiac disease on gluten free diet

Exclusion Criteria:

• acute or chronic diseases,
• permanent use of medication and
• ingestion of antibiotics at least one month prior to study