Coeliac disease can be diagnosed in some adults with just a blood test, according to interim guidance from the British Society of Gastroenterology (BSG).

The latest information comes in the wake of concerns that the usual two-step procedure, a blood test in search of antibodies followed by an endoscopy with biopsy to look for intestine damage, left patients exposed to coronavirus infection.

In the early stages of the pandemic, the BSG recommended non-emergency endoscopies be paused to shield NHS staff and patients from Covid-19, a move that left many people suspected of having coeliac unable to access their usual, full diagnostic treatment.

The latest guidance comes ahead of publication of the BSG’s coeliac guidelines next year.

It says adults under 55 who do not need an endoscopy to rule out other conditions, have antibody levels (IgA tissue transglutaminase) at least 10 times the upper limit of normal and a second positive antibody blood test (endomysial antibodies (EMA) or tissue transglutaminase if EMA isn’t available) can have a no-biopsy diagnosis.

It also says a GP can request an initial antibody blood test but a gastroenterologist should decide if an endoscopy and biopsy is needed and make the final diagnosis of coeliac disease.

“Coeliac UK has previously called for the national guidelines to review the evidence for adult no-biopsy diagnosis and so fully supports the BSG’s new position,” said the charity's chief executive Hilary Croft.

“This will enable a greater number of people to gain a faster diagnosis, without the need to wait for an endoscopy at the hospital.

“Getting an accurate diagnosis of coeliac disease means keeping gluten in the diet throughout the testing process - a difficult feat when waiting lists are long and people feel unwell.”

About half a million people in the UK have undiagnosed coeliac, an autoimmune disease which causes the body’s immune system to damage the lining of the small bowel when gluten is eaten, according to Coeliac UK.

The symptoms of coeliac have often been confused with irritable bowel syndrome or wheat intolerance.