Esophagus to Small Intestine
Gastroenterology. 2024;166(4):620–30
Accuracy of the no-biopsy approach for the diagnosis of celiac disease in adults: A systematic review and meta-analysis
Background and aims: Current international guidelines recommend duodenal biopsies to confirm the diagnosis of celiac disease in adult patients. However, growing evidence suggests that immunoglobulin A (IgA) anti-tissue transglutaminase (tTG) antibody levels ≥ 10 times the upper limit of normal (ULN) can accurately predict celiac disease, eliminating the need for biopsy. The authors performed a systematic review and meta-analysis to evaluate the accuracy of the no-biopsy approach to confirm the diagnosis of celiac disease in adults.
Methods: They systematically searched Medline, Embase, Cochrane Library, and Web of Science from January 1998 to October 2023 for studies reporting the sensitivity and specificity of IgA-tTG ≥ 10 x ULN against duodenal biopsies (Marsh grade ≥ 2) in adults with suspected celiac disease. A bivariate random effects model was used to calculate the summary estimates of sensitivity, specificity, and positive and negative likelihood ratios. The positive and negative likelihood ratios were used to calculate the positive predictive value of the no-biopsy approach across different pretest probabilities of celiac disease. The methodological quality of the included studies was evaluated using the QUADAS-2 tool.
Results: A total of 18 studies comprising 12,103 participants from 15 countries were included. The pooled prevalence of biopsy-proven celiac disease in the included studies was 62% (95% confidence interval [CI]: 40–83%). The proportion of patients with IgA-tTG ≥ 10 x ULN was 32% (95% CI: 24–40%). The summary sensitivity of IgA-tTG ≥ 10 x ULN was 51% (95% CI: 42–60%), and the summary specificity was 100% (95% CI: 98–100%). The area under the summary receiver-operating characteristic curve was 0.83 (95% CI: 0.77–0.89). The positive predictive value of the no-biopsy approach to identify patients with celiac disease was 65%, 88%, 95%, and 99% if celiac disease prevalence was 1%, 4%, 10%, and 40%, respectively. Between-study heterogeneity was moderate (I2 = 30.3%), and additional sensitivity analyses did not significantly alter these findings. Only 1 study had a low risk of bias across all domains.
Conclusion: The results of this meta-analysis suggest that selected adult patients with immunoglobulin A anti-tissue transglutaminase antibody levels ≥ 10 times the upper limit of normal and a moderate to high pretest probability of celiac disease could be diagnosed without undergoing invasive endoscopy and duodenal biopsy.