Are we diagnosing too many people with coeliac disease?

Serum transglutaminase antibodies do not always detect the persistent villous atrophy in patients with celiac disease on a gluten-free diet

BACKGROUND AND AIM

Serum transglutaminase antibodies (tTGs) are used for celiac disease screening and to monitor celiac disease patients on a gluten-free diet (GFD). The need for histology of duodenal biopsies to assess mucosal healing after a GFD is still a matter of debate. We evaluated whether tTGs are adequate to detect the persistence of histological lesions of duodenal mucosa in celiac patients after a GFD.

METHODS

In total 253 patients with histological diagnosis of celiac disease according to Marsh criteria, both at the time of diagnosis (T0) and 18-24 months after starting a GFD (T2), were included. tTGs were evaluated both at T0 and T2; endomysial antibodies (EMAs) only at T0.

RESULTS

At T0, 9.2% of patients had both tTG and EMA negative values, despite the evidence of duodenal lesions: 33.3% of Marsh 1, 14.3% of Marsh 2 and 5.2% of Marsh 3. At T2, tTGs were negative in 77.6% of patients: 82.2% of Marsh 0, 79.8% of Marsh 1, 70.0% of Marsh 2 and 59.1% of Marsh 3. At T2, approximately 60% of patients with the persistence of mucosal atrophy had negative tTGs. At T0, tTG median values were lower in patients with Marsh 1 and Marsh 2 than patients with Marsh 3 (P < 0.001), whereas no difference was found at T2 regardless of Marsh's grade (P = 0.4).

CONCLUSIONS

The results of our study highlight how histologic evaluation of duodenal biopsies remains the gold standard for both celiac disease diagnosis and the evaluation of mucosal recovery after 18-24 months of a GFD.

Value of routine duodenal mucosal biopsies in the evaluation of anemia in a large Australian referral centre

Background and Aim

Small bowel mucosal biopsies (SBBx) are routinely performed to investigate unexplained anemia; however, previous studies have demonstrated a low yield in diagnosing celiac disease. Our aim was to determine the yield of routine SBBx in a large cohort of patients who underwent gastroscopy for the investigation of anemia.

Methods

Data from consecutive patients who underwent gastroscopy for the investigation of anemia in a tertiary hospital, from January 2008–December 2011, were prospectively collected. Measured outcomes were the prevalence of celiac disease, the yield of duodenal biopsies, and the correlation between celiac serology and diagnosis.

Results

Over 4 years, 987 patients (385 M:602 F; 48.27 ± 15.89 years) underwent endoscopy for anemia, of which 534 (54.1%) had proven iron deficiency anemia (IDA). Abnormal SBBx consistent with celiac disease were found in 2% (22/987), with a higher prevalence in females (3.2%, n = 19 vs 0.8%, n = 3 in males) and in those with IDA (3.6%, n = 19 vs 0.7%, n = 3 in non‐IDA). Macroscopic endoscopic abnormalities were present in 86% (19/22) of patients with celiac disease. Of the 178 patients who had celiac serology, tissue transglutaminase antibody had the highest sensitivity (80%) and specificity (99%). Combined serology had a sensitivity of 85.7%.

Conclusion

Only 2% of patients with unexplained anemia had abnormal SBBx consistent with celiac disease and even fewer patients in non‐IDA. Given the availability and high sensitivity of celiac serology and macroscopic changes on endoscopy, SBBx should not be routine during endoscopy but should be limited to those with positive celiac serology, abnormal endoscopic appearance, or females with IDA.