During acid reflux, acid moves from the stomach back into the food pipe (oesophagus), which can cause inflammation. You may feel heartburn behind your breastbone.

But oesophageal inflammation isn’t always caused by acid. In some people, eosinophils accumulate in the lining of the oesophagus, leading to inflammation.

The condition, known as eosinophilic oesophagitis (EoE), was only formally recognised in the 1990s. It’s commonly confused with GERD symptoms like heartburn, but it is now recognised as an important cause of oesophageal disease. Due to its fairly recent discovery, our understanding of the condition and its treatment is continually evolving.

What Is Eosinophilic Oesophagitis (EoE)?

Oesophagitis simply means inflammation in the oesophagus. Eosinophilic oesophagitis means that when visualised, the lining of the inflamed oesophagus contains lots of eosinophils, which are a type of white blood cell.

It’s not completely clear why EoE occurs. Some researchers have suggested it’s due to your genetic makeup and the body’s response to environmental factors. Eosinophils are commonly implicated in asthma and hay fever. People with these conditions are more likely to develop EoE.

Why EoE Is Often Mistaken for Acid Reflux

Eosinophilic oesophagitis is often confused with acid reflux because both can cause discomfort behind the breastbone, difficulty swallowing, and regurgitation. When patients present with these symptoms, doctors are quick to assume it's acid reflux, which is the more common condition.

Patients may be prescribed antacids or even acid suppression medications like PPIs. However, symptoms usually do not improve with standard reflux medication, which targets acid rather than the underlying oesophageal inflammation. The patient is then often sent for an endoscopy, where eosinophilic inflammation is identified.

Common Symptoms of Eosinophilic Oesophagitis

The symptoms of EoE vary by age group.

You may notice:

Adults

• Difficulty swallowing (dysphagia)

• Food getting stuck in the oesophagus after swallowing (food impaction)

• Chest pain, often centrally located and not relieved by antacids

• Backflow of undigested food (regurgitation)

Children

• Difficulty feeding in infants

• Difficulty eating in older children

• Vomiting

• Abdominal pain

• Difficulty swallowing (dysphagia)

• Food getting stuck in the oesophagus after swallowing (food impaction)

• Symptoms that do not respond to GERD medications

• Failure to thrive, including poor growth, malnutrition, or weight loss

What Causes EoE?

The exact cause isn’t fully understood. Given the overlap with allergic (atopic) conditions such as asthma, eczema, and hay fever, it’s believed that EoE is triggered by food or environmental allergens. Common triggers may include dairy, wheat, eggs, soy, nuts, or seafood.

Most similar conditions have a strong genetic predisposition. A specific genetic cause hasn’t yet been identified in EoE, but researchers believe a genetic component is likely.

How EoE Is Diagnosed

Most patients with EoE visit their doctor because of persistent symptoms. Their doctor will usually begin with a medical history and symptom review. In many cases, acid-suppressing medication is prescribed first. However, if difficulty swallowing is severe, the patient may be referred for an endoscopy to examine the oesophagus.

During an endoscopy, a biopsy of the oesophageal lining is taken and sent to the laboratory for analysis of eosinophil accumulation.

Because EoE symptoms can resemble acid reflux, the condition often goes undiagnosed for longer than other digestive disorders. Some patients remain on acid-suppressing medication for months before the correct diagnosis is made. This is why testing for acid reflux can be useful to rule it out.

The Functional Gut Clinic offers 24-hour acid reflux testing to determine whether reflux is actually occurring. This can help narrow down the cause of your symptoms and identify whether EoE may be involved.

Treatment Options for Eosinophilic Oesophagitis

Eosinophilic oesophagitis is considered a chronic relapsing condition. Most patients will require ongoing treatment to control their symptoms.

Because EoE is linked to allergic reactions, the best approach is to identify potential triggers. That could mean cutting out foods such as dairy or wheat to reduce inflammation.

Other treatments include:

• Proton pump inhibitors (PPIs), often used as a first-line treatment. Some patients with EoE respond well to these medications, although others require additional therapies.

• Topical steroids, such as fluticasone or budesonide, can be swallowed and are designed not to be absorbed into the bloodstream.

• Monoclonal antibodies like dupilumab (Dupixent) offer a potential treatment. These medications work by blocking certain proteins responsible for inflammation.

When to See a Doctor

Difficulty swallowing (dysphagia) is always a concerning symptom. While EoE isn’t a severe condition, even if it is chronic, other causes of dysphagia can be life-threatening. You should always see a doctor if you notice any of these symptoms:

• Frequent difficulty swallowing

• Food getting stuckacid reflux

• Persistent reflux symptoms despite treatment

• Unexplained chest pain

Early treatment for EoE can prevent long-term complications. If left untreated, it can lead to oesophageal scarring or narrowing, which may require a procedure called dilatation.

If you have persistent reflux symptoms or difficulty swallowing, it’s important to investigate the cause.

The Functional Gut Clinic offers advanced reflux testing and specialist assessments to help rule out whether acid reflux is the cause of your symptoms, or if further investigations are needed.

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