Celiac Disease Screening

Our overall hypothesis is that first and second degree relatives of individuals with celiac disease benefit from screening and diagnosis of celiac disease. Secondary hypotheses are: 1. The number needed to test and cost to benefit one person though celiac disease screening are within acceptable ranges of 33 tested and \< $10,000 spent. 2. Treatment does not lead to adverse metabolic changes. 3. Intestinal biopsy is unnecessary for accurate diagnosis in a substantial subset of adults. Aim 1. Determine the effect of screen detected celiac disease on health related quality of life. * Evaluate change in health related quality of life at one year in participants randomized to the screen detected, early diagnosis cohort compared to the screen detected, delayed diagnosis, clinically detected and non-celiac control cohorts. * Evaluate change in symptoms, psychological well-being and burden of treatment at one year in the screen detected, early diagnosis cohort compared to the screen detected, delayed diagnosis, clinically detected and non-celiac control cohorts. * Evaluate the cost per diagnosis and the number needed to test for the diagnosis of individuals who will have a clinically meaningful improvement in health related quality of life attributable to treatment of celiac disease. Aim 2: Assess the effect of screen detected celiac disease on nutritional and metabolic indices. * Compare changes bone density, body mass index, Reynolds Cardiovascular Risk Score, and nutritional indices at one year in the screen detected, early diagnosis cohort compared to the screen detected, delayed diagnosis, clinically detected and non-celiac control cohorts. Aim 3: Evaluate the reliability of using serologic tests in combination with intestinal fatty acid binding protein vs. intestinal biopsy to confirm celiac disease diagnosis in adults. * Prospectively assess the sensitivity and specificity of a novel non-invasive celiac diagnostic algorithm in comparison to the current gold standard of small intestinal biopsy histology. * Model the cost of modified, non-invasive celiac testing vs. classical testing with endoscopic biopsy in both screen-detected and clinically identified celiac disease.