What is eosinophilic gastroenteritis?

Eosinophilic gastroenteritis (EGE) is a rare but increasingly recognised digestive condition in which eosinophils — a type of white blood cell involved in allergic and immune reactions — build up excessively in the lining of the digestive tract.¹˒² Depending on which part of the gut is affected and how deep the inflammation goes, symptoms can vary from mild abdominal discomfort to severe nutritional problems or bowel obstruction.³˒¹⁰⁻¹²

Common symptoms include:

• Abdominal pain
• Nausea and vomiting
• Chronic diarrhoea
• Unexplained weight loss
• Bloating or swelling
• Protein loss into the gut (protein-losing enteropathy)
• Anaemia or low blood counts

EGE can occur at any age, affecting both children and adults. Because its symptoms often resemble those of irritable bowel syndrome (IBS) or food intolerances, many people experience delays in diagnosis.²

Why clinical symptoms alone are not enough

EGE shares its symptoms with many other gut disorders, including coeliac disease, Crohn’s disease, and inflammatory bowel disease (IBD).³˒⁵˒⁶˒⁹ Fatigue, nausea, diarrhoea, and abdominal pain are common in all of these, which makes diagnosis based on symptoms alone unreliable.

Even blood and stool tests rarely provide a clear answer, and allergy testing can miss the diagnosis entirely.⁵˒⁶ Because eosinophilic inflammation cannot be seen with scans or predicted from routine tests, the only reliable way to confirm EGE is through a biopsy — a direct tissue examination from the stomach or intestines.¹˒²

The science: why multiple biopsies matter

EGE is a patchy disease, meaning the inflammation is not evenly distributed throughout the gut.

• Taking multiple biopsies greatly improves the chance of detection¹˒²
• Studies show that 8–12 biopsies are needed to identify all cases of EGE. Taking fewer samples can lead to missed diagnoses¹
• In one study, 92% of patients had a normal endoscopic appearance, proving that relying only on visibly abnormal areas can miss most cases¹

Diagnostic criteria

Pathologists look for 30 or more eosinophils per high-power microscopic field in at least five areas (or three for the duodenum).² Additional signs such as swelling, fibrosis, and tissue damage support the diagnosis.

What else can a biopsy reveal?

A biopsy does more than confirm EGE — it can also rule out other diseases that mimic its symptoms, such as:

• Gut infections and parasites²˒⁵
• Cancers or pre-cancerous changes⁴˒⁷
• Inflammatory or autoimmune bowel disorders⁵˒⁶˒⁹
• Coeliac disease and other gluten-related conditions⁶
• Microscopic colitis²

By excluding these, doctors can provide treatment based on evidence rather than guesswork.

What happens if EGE Is missed?

Without a biopsy, EGE may go undiagnosed for years, leading to:

• Persistent digestive symptoms
• Unnecessary medications or procedures
• Malnutrition and weight loss
• Risk of intestinal blockage if deeper gut layers are affected²

Timely diagnosis through biopsy can prevent these complications and lead to earlier, more effective treatment.

Treatment after diagnosis

Once EGE is confirmed, treatment is individualised based on symptom severity. Common options include:

• Steroids (oral or topical) to reduce inflammation²
• Dietary changes, such as elimination diets to identify trigger foods²
• Biologic therapies, which are newer treatments used for severe or resistant cases

Because the disease can relapse, follow-up biopsies may be recommended to check for remission or recurrence.¹˒²

Evidence supporting biopsy

• A landmark study of 98 patients found that comprehensive, multi-site biopsy protocols were essential for detecting all EGE cases.¹
• The American College of Gastroenterology and international consensus groups now consider biopsy mandatory for diagnosis.¹
• Even when eosinophilic oesophagitis (EoE) is suspected, biopsies from the stomach and duodenum are required to rule out EGE and similar disorders.¹

Biopsy safety and practical tips

Endoscopic biopsy is very safe, with serious complications such as bleeding or infection occurring in less than 1% of cases.⁸ However, false negatives can occur if too few biopsies are taken or if only abnormal-looking areas are sampled.

Practical advice:

• Request multiple biopsies from different parts of the stomach and duodenum¹˒²
• If results are unclear, ask for a second opinion or referral to a specialist centre familiar with EGE

Summary

Eosinophilic gastroenteritis is a complex and often underdiagnosed condition. Symptoms and blood tests alone cannot confirm it — only a biopsy can provide a definitive diagnosis.¹˒²

Taking multiple, well-placed biopsies during endoscopy ensures accurate detection, helps rule out other conditions, and allows for targeted treatment. If you have ongoing digestive symptoms without a clear explanation, speak to your GP about seeing a gastroenterologist for further assessment. Early diagnosis makes a real difference in recovery and long-term health.

Frequently asked questions

How many biopsies are needed for diagnosis?

At least 8–12 biopsies from the stomach and duodenum are recommended to detect all cases and avoid false negatives.¹˒²

Can blood tests or scans diagnose EGE?

No. There are no blood or imaging tests that can confirm EGE — only a biopsy can provide certainty.¹˒²

What does a positive biopsy show?

It shows clusters of eosinophils — typically 30 or more per microscopic field — along with signs of inflammation or tissue damage.¹˒²

Is a biopsy painful or risky?

Biopsies are performed under sedation and are generally painless. Serious complications, such as bleeding or infection, occur in less than 1% of cases.⁸

Should children have a biopsy if EGE is suspected?

Yes. Children can also develop EGE, and their symptoms are often nonspecific. Biopsy ensures accurate diagnosis and appropriate treatment.²