Role of Duodenal Bulb Biopsy in Diagnosing Suspected Celiac Disease in Adult Patients: A Systematic Review and Meta-analysis.

Background and aims: Current guidelines recommend multiple biopsies from the first (D1) and second (D2) part of duodenum to establish a diagnosis of celiac disease. In this meta-analysis we aimed to find whether D1 biopsy can increase the diagnostic yield of adult celiac disease.

Methods: Literature databases were searched until January 2023 for studies reporting diagnosis of celiac disease in the adult population using D1 biopsy. Meta-analysis was done using a random-effects model. Heterogeneity was assessed by I 2 % and 95% prediction interval statistics. Measured outcomes were diagnostic yield with D1 and D2 biopsies and from 4 versus 2 biopsy samples.

Results: A total of 16 studies were included in the final analysis. The pooled diagnostic rate of celiac disease from D1 biopsy was 77.4% [95% CI (64.7-86.5, I 2 94%)] and from D2 biopsy was 75.3% [60.8-85.7, I 2 96%]. The pooled rate of increase in diagnostic yield with D1 biopsy was 6.9% I [4.6-10.2, I 2 66%]. The pooled diagnosis rate with 2 biopsy samples were 77.3% [50-92, I 2 93%] and 86.4% I [58.4-96.7, I 2 87%] from D1 and D2 respectively, whereas that with 4 biopsy samples were 83.3% [49.8-96.2, I 2 76%] and 70.5% I [51-84.6, I 2 96%] from D1 and D2, respectively, the difference being non-significant.

Conclusion: Our study demonstrates that taking 4 biopsy samples does not incur any additional diagnostic value over taking 2 biopsy samples from each duodenum segment. Although biopsy from the D1 and D2 has similar diagnostic yield in the adult population, there was an overall increase in diagnostic yield with D1 biopsy, especially in those with a patchy disease distribution.