A prospective, longitudinal study meant to compare blood levels of I-FABP in pediatric celiac patients during diagnosis to levels under gluten free diet, it's correlation with traditional serology testing and questionnaire regarding patient responsiveness to the gluten free diet, and in comparison to a control group.

I-FABP is a reliable marker for intestinal damage and has been proved to respond more swiftly than traditional serology to enterocyte injury in celiac patients who do not a gluten free diet. In this study a pediatric population of celiac patients will be tested for I-FABP levels during initial endoscopic diagnosis and during one year of follow up. Their levels will be compared to a control group of pediatric patients undergoing endoscopy for reasons other than suspicion of celiac disease. During the period of follow up, the test group will undergo repeat testing for I-FABP levels, as well as the traditional follow up testing for serology in celiac patients and a questionnaire regarding. The results will be analyzed in the hope of finding a way to use I-FABP as a more direct, accurate marker of disease activity, and of correlations between it's level and the patient's Marsh score at diagnosis.

Inclusion Criteria:

• Children undergoing endoscopy for diagnosis of celiac disease, with elevated serology (TTG more than 3 times the norm), and whose histological Marsh score is 2 or higher.

Exclusion Criteria:

• Diseases known to cause elevation in I-FABP levels: Bowel ischemia, inflammatory bowel disease, Primary Biliary Cholangitis, liver failure, biliary duct obstruction, liver malignancy.
• Bowel trauma or abdominal surgery or acute gastroenteritis in the last 3 months
• NSAID use in the last week.
• Intensive daily physical activity (over 1 hour) in the 2 days prior to endoscopy.
• Known genetic disorders (such as Down's syndrome).
• Patients whose TTG was elevated but lower than 3 times the normal range.

Pediatric patients undergoing endoscopy at the research hospital.