BSG Interim Guidance: COVID-19 specific non-biopsy protocol for those with suspected coeliac disease

Our advice and guidance around COVID-19 is being regularly reviewed. Visit https://www.bsg.org.uk/covid-19-advice/ to see the latest published guidance.

In guidance on restarting endoscopy services the BSG has suggested treating patients (< 55 years) with suspected coeliac disease and a tTG >x10ULN without biopsy.

Here is the protocol further detailing this advice, which is specific to the COVID-19 environment and has been issued as interim guidance pending the publication of the new BSG Coeliac Guideline expected to be published in 2022.

COVID-19 Non-biopsy policy for adults with positive coeliac serology

BSG Suggested Protocol Pending Revisions of the BSG Coeliac Disease Guidelines

Penny HA, Sanders DS, Gillett H, Gillett P, Edwards CM.

What we know about using non-biopsy protocol to date:

There is emerging evidence that an IgA tissue transglutaminase (tTG) level of ≥10x the upper limit of normal (ULN) is more than 90% predictive of villous atrophy in the adult population.
In children, EMA testing in a second blood sample serves to reduce the likelihood of a false-positive tTG result and/or the possibility of a recording a transiently elevated tTG titre. Where EMA is not available a 2^nd tTG is acceptable.
HLA DQ2 and DQ8 is only of value for excluding coeliac disease and testing does not appear to improve the predictive value of this approach.
There is an unknown risk to undiagnosed individuals who have coeliac disease but are not on a GFD. This is likely to be comparable to a patient with coeliac disease that has on-going villous atrophy.
The risks are of increased haematinic deficiency, reduced bone mineral density, reduced quality of life and increased risk of small bowel lymphoma.

Penny H et al Progress in the serology-based diagnosis and management of adult coeliac disease. Expert Rev Gastroenterol Hepatol 2020;13:1-8. doi: 10.1080/17474124.2020.1725472. Werkstetter et al Gastroenterology 2017 doi.org/10.1053/j.gastro.2017.06.002

The essential practice points of using a non-biopsy protocol in adults:

COVID-19 Specific Advice

Advise patients that:

There is no increased risk to them with coeliac disease
Splenic hypofunction is a theoretical risk and that no patients with coeliac disease have been reported to date to have had increased risk of COVID-19
If a patient has refractory coeliac disease then there could be an increased risk in terms of severity of COVID-19 infection were they to become infected
Those on immunosuppressants should shield if they have refractory disease and are taking 20mg or more daily of Prednisolone (see IBD Risk grid for more information)

Considerations for Units

All referrals to secondary care for endoscopy, because of positive coeliac serology, should be tracked and allocated to secondary care triage review at 3-6 months
Outcomes need to be audited by secondary care as a result of this virtual triage
Suggest local TTG assay reliability needs correlating to pathology as part of any local audit

Opportunity to participate in a Service Evaluation

Following the launch of this new diagnostic pathway, we are proposing to undertake a prospective service evaluation to gather data concerning the appropriateness and impact of this approach.

The aim will be for interested parties at sites across the country to collect local data (details tbc) on all individuals with raised tTG values. This will enable us to address the following key questions (among others):

What are the performance characteristics of this pathway across different sites? (determined from those who have tTG values ≥10xULN and proceed to biopsy due to age and/ or presence of red flag symptoms)
What proportion of the patients diagnosed using a biopsy avoidance approach re-present to secondary care with ongoing symptoms for further investigations, and what is the outcome?
What conditions would we miss if we did not scope the >55 year olds and those with red flag symptoms?
Are there any groups who get scoped even if they have potential for a serology-based diagnosis?
How beneficial is this approach (e.g. patient friendly, reduced delays to GFD, cost effectiveness, endoscopies saved)?

This represents an opportunity for anyone interested to get involved in the development and implementation of a new diagnostic pathway for adult coeliac disease. Clinical and laboratory staff of any level are welcome. For more information please contact h.penny@sheffield.ac.uk.

Dr Cathryn Edwards MA D.Phil FRCP

BSG President June 2018-June 2020