In some corners, experts have suggested the need for a followup intestinal biopsy to assure that celiac disease is responding to a gluten-free diet (Related blog post: Are followup biopsies necessary in celiac disease? Look beyond the headlines). Meanwhile, many are looking at performing zero biopsies –at diagnosis or later. A recent study (J Wolf et al. Gastroenterol 2017; 153: 410-9) involved a prospective enrollment of 898 children undergoing duodenal biopsy to confirm or rule out celiac disease (CD). Patients had tissue transglutaminase IgA (TTG IgA), total IgA and deamidated gliadin IgG (DGL-IgG) measured.
- 592 had CD and 345 did not have CD. 24 did not have a final diagnosis.
- In examining non-IgA deficient patients that had either TTG IgA >10 times ULN or normal (<1 times ULN), the positive predictive value for CD was 0.988 and the negative predictive value was 0.934.
- In examining patients with both TTG IgA elevation (>10 times ULN) and DGP-IgG (>10 times ULN) or normal labs, the positive predictive value (PPV) for CD was also 0.988 and the negative predictive value (NPV) was 0.958. The authors estimated that the PPV and NPV would remain >0.95 even at disease prevalence rates as low as 4%.
- In this high prevalence population, the authors note that only 23% would have required an endoscopy to confirm or exclude CD; however, they note that in another study using consecutive serologic data, a much higher proportion (57%) needed biopsies due to serology that was <10 times ULN.
- The authors note that HLA status genotyping, which has been recommended as needed in non-biopsy diagnosis, is not helpful. Compatible HLA status was noted in all 277 cases of TTG-IgA >10 times ULN and was deemed “unnecessary” by the study authors in those with high titers.
The ESPGHAN guidelines for non-biopsy diagnosis indicate that a repeat serologic study should be performed to exclude a sample mix-up and to only forego biopsies in symptomatic patients.
My take: This study show\ed that individuals with high celiac serology titers have celiac disease >98% of the time. This information should be discussed with families in determining whether endoscopic biopsy is needed. Among those who pursue a non-biopsy approach, some individuals could have competing etiologies for their symptoms; thus, a low threshold for evaluation is needed in those who do not respond to a gluten free diet
Related blog posts:
- To biopsy or not to biopsy -that is the question (for Celiac disease)
- How Accurate is Serology at Predicting Mucosal Healing in Celiac Disease
- Drug Therapy for Celiac Disease | gutsandgrowth
- Why is Celiac Disease Becoming More Prevalent? | gutsandgrowth
- Benefits of Gluten–Free Diet for “Asymptomatic” Celiac | gutsandgrowth
- Closer followup for Celiac disease & pediatric … – gutsandgrowth
Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician. This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.