Celiac Disease: Ten Things That Every Gastroenterologist Should Know

Amy S. Oxentenko; Joseph A. Murray


Clin Gastroenterol Hepatol. 2015;13(8):1396-1404. 

In This Article

4. Which At-risk Patients Should Be Tested for Celiac Disease?

First-degree relatives, especially siblings, of those with CD are at increased risk of CD.[24–27] When sibling pairs have CD, the familial risk is further elevated.[28] It is controversial whether asymptomatic family members should be tested. However, supposedly asymptomatic family members diagnosed with CD often uncover ill health that improves on a GFD.[29] Therefore, it is reasonable to consider testing all first-degree relatives.[3] Providers should, at minimum, assess for clinical features of CD among relatives. In families with affected sib pairs, all first-degree and second-degree relatives should be tested. Any family member with features of CD requires duodenal biopsies even if seronegative.[30] HLA testing is less helpful in family members because of the high likelihood of at-risk HLA alleles.[31]

CD is more common in type 1 diabetes mellitus (T1DM), with higher prevalence in children (3%–8%) compared with adults (2%–5%).[30,32] Both conditions share the same HLA DQ2/8 alleles. Although some suggest that all patients with T1DM be screened for CD,[33] most recommend testing only symptomatic patients.[30,34] However, patients with T1DM and features of CD or repeated hypoglycemia should be evaluated. In any patient with T1DM presenting for upper endoscopy, duodenal biopsies could be considered.[30] Because of the shared HLA alleles between CD and T1DM, screening should be done with serology. Duodenal biopsies should be performed if there is high concern of CD despite negative serologies. Screening for CD is not routinely recommended in those with thyroid and other autoimmune conditions unless there are features of disease.[30]

Patients with Down's syndrome are 5 times more likely to develop CD compared with the general population,[30] although prevalence rates vary.[35] Although there is not uniform consensus regarding screening for CD in those with Down's syndrome,[36] there is agreement that patients with CD features be evaluated. One approach in Down's syndrome is to first test for permissive haplotypes (HLA DQ2 and DQ8), and if absent, future testing is unnecessary.[36] In those with permissive haplotypes, serologic surveillance is suggested. It is not known whether repeat future testing is needed. Patients with Turner's and Williams' syndromes are also at increased risk of CD.[37,38]

Practical Suggestion

Consider serologic testing for all first-degree relatives of a patient with CD, even those apparently asymptomatic. Test relatives of affected sib pairs. Test symptomatic (and consider screening asymptomatic) patients with T1DM and Down's, Turner's, and Williams' syndromes by using serology in diabetic patients and HLA haplotyping in those with chromosomal abnormalities. In these patients, diagnostic testing should be the terminology used rather than screening to ensure insurance coverage.