Researchers are encouraging relatives of people who have been diagnosed with celiac disease to get tested after a study revealed that a significant number of these relatives have undiagnosed cases of celiac themselves. The study has also suggested that screening guidelines for celiac disease should reflect these findings, and when new celiac patients are identified, their first degree relatives should be tested. The findings have been reported in the Medical Journal of Australia.
Celiac disease is a condition in which the consumption of gluten, which is a protein that is found in barley, rye, and wheat, causes an immune reaction in the small intestine. This can cause bloating, diarrhea, or fatigue. Over time, these immune reactions can damage the lining of the small intestine and lead to a host of other problems, including the malabsorption of nutrients, anemia, and weight loss. There is no cure for celiac disease and patients have to avoid eating gluten. If diagnosis is delayed, celiac may also cause infertility, osteoporosis, and small bowel cancer.
In this study, the researchers wanted to know whether testing relatives of celiac patients would be beneficial. They assessed 202 people who are either parents, siblings, or children of 134 different celiac disease patients; they used tests that analyzed genes that contain celiac disease risk factors, and performed small bowel biopsies when possible.
Genotyping for human leukocyte antigens HLA can be done, and negative tests for two alleles of HLA genes called HLA-DQ2 and HLA-DQ8 make celiac disease highly unlikely.
This work revealed that seven of the 62, or about 11 percent of people who were children of celiac disease patients also had celiac, which was confirmed by small bowel biopsy, the standard test for the disorder. About 14 percent of the relatives who carried genotypes that indicate an increased risk of celiac were confirmed to have the disease.
Celiac disease may have genetic components, so there is a heritable aspect to the disease. Previous studies have suggested that one in 22 first degree relatives, who are parents, children, or siblings of celiac patients also have the disease. About one in 39 second degree relatives, or aunts, uncles, and grandparents, also have the disease.
"The most important outcome of this study will be if it highlights the need for first degree relatives of people with celiac disease to be screened for celiac disease themselves," said lead study author Dr. James Daveson of the Wesley Research Institute.