Screening for coeliac disease (CD) in affected families reveals a high prevalence of the disease including in people who are asymptomatic or have non-classic symptoms.
A retrospective US study of 104 patients with CD and 360 of their parents, siblings and children, found 44.4% of first degree relatives (FDRs) screened positive for CD using anti-tissue transglutaminase titres.
The study found 65.5% of the screen-positive family members had a non-classic presentation, 28.4% were asymptomatic and only 6.1% had classic symptoms.
On average, screening identified 4.6 affected FDRs per family.
Only 18 individuals (10%) who screened positive were not confirmed with coeliac disease at biopsy.
There was a high correlation between anti-TTG titres and villous atrophy regardless of symptom status. Children had higher anti-TTG titers than adults.
Where histology reports were available in the FDRs, the findings had a similar pattern to those seen in the index cases – Marsh 1 (7.7% v 11.8%), Marsh 3a (49.7% v 39.8%) and Marsh 3b (42.6% v 48.4%).
The study, from the Mayo Clinic, said the US Preventive Services Task Force suggests only symptomatic FDRs should be tested.
However, the high rate of asymptomatic presentation in FDRs suggested “early and proactive screening” led to earlier diagnosis.
“Our results are consistent with previous studies among FDRs that showed higher rates of asymptomatic CD than symptomatic CD and lack of association between symptoms and the degree of VA, whereas higher anti-TTG titer correlated with a higher degree of VA.”
“Based on high prevalence of positive anti-TTG titers between screened FDRs noted in our cohort and previous studies, we suggest that FDRs must be screened regardless of symptoms,” the study said.
“Furthermore, gastroenterologists and general practitioners should ask about family history of CD among their patients’ FDRs and consider screening them for CD if present.”
The study said prospective studies were required to confirm the predictive value of anti-TTG titres as a diagnostic test among FDRs with the possibility of foregoing confirmatory biopsy.