BSG 2026 Selected Adults Can Now Be Diagnosed With Coeliac Disease Without Biopsy: Gut | July 2026

Introduction:

Adult coeliac disease has traditionally required duodenal biopsy for diagnostic confirmation, even when serology is strongly positive. The 2026 BSG guideline introduces an important change: carefully selected symptomatic adults can now be diagnosed without biopsy when serological evidence is sufficiently strong.

Why was this guideline needed?

Adult diagnosis has traditionally depended on endoscopy and duodenal histology.

Very high tTG-IgA levels have strong diagnostic accuracy for coeliac disease.

Mandatory biopsy can delay diagnosis and increase endoscopy burden.

A standardised pathway was needed to identify adults in whom biopsy can be safely avoided.

Key Takeaways:

A no-biopsy diagnosis can be considered in selected symptomatic adults assessed in secondary care.

The key serological threshold is IgA tTG ≥10× the assay upper limit of normal (ULN).

The decision should follow appropriate clinical assessment and discussion with the patient.

The pathway is not intended for every patient with positive coeliac serology.

It should not simply be extrapolated to unsupervised primary-care diagnosis.

Upper GI endoscopy remains appropriate when there are red-flag symptoms or diagnostic uncertainty.

Endoscopy should also be performed when another clinical indication for upper-GI evaluation exists.

Patients who do not meet the defined no-biopsy criteria should continue through the conventional diagnostic pathway including duodenal histology.

The guideline combines GRADE-based recommendations with good-practice and expert-opinion statements, reflecting areas where evidence remains limited.

What’s New?

The major change is a move away from mandatory histological confirmation in every adult toward a carefully selected serology-based diagnosis when tTG-IgA is ≥10× ULN.

Bottom Line:

BSG 2026 introduces a major shift in adult coeliac diagnosis: selected symptomatic adults with tTG-IgA ≥10× ULN may avoid duodenal biopsy. The pathway requires appropriate specialist assessment and should not be applied indiscriminately to all patients with positive serology.