Eosinophilic Oesophagitis (EO)

• What is Eosinophilic Oesophagitis (EO)?
• Statistics
• Risk Factors
• Progression
• Symptoms
• Clinical Examination
• How is it Diagnosed
• Prognosis
• Treatment
• References

What is Eosinophilic Oesophagitis (EO)?

Eosinophilic oesophagitis (EO), also known as eosinophilic esophagitis (EE), is a specific inflammatory condition of the oesophagus where the wall becomes filled with eosinophil cells. The oesophagus is the muscular tube extending from the throat to the stomach which is important in swallowing. Eosinophils are a specific type of white blood cell involved in inflammatory changes, particularly those associated with allergic reactions.

Statistics

EO was first reported in 1978 and now is recognised worldwide. The incidence of EO appears to be increasing along with a range of other allergic disorders in developed countries. A Western Australian study showed the incidence of EO in kids increased by a factor of almost 18 from 1995 to 2004. In recent years there has been increasing recognition of the disease in adults.

For unknown reasons EO is more common in men who are affected approximately three times more commonly than women. The majority of patients with EO are therefore young boys or men.

Risk Factors

The exact cause of EO is not known. Studies have shown that food allergy (in particular to cow’s milk, soy, wheat and egg) may be associated with the disorder. Approximately 68% of patients will have other allergic disease such as rhinitis, bronchial asthma and atopic dermatitis.

Other contributory factors may include genetics, environmental antigens or abnormal immunological responses.

Progression

EO can present in a variety of ways. In young children symptoms are usually similar to those of gastro-oesophageal reflux disease (GORD) such as upper abdominal pain, regurgitation, vomiting or chest pain. During adolescence symptoms of dysphagia (difficulty swallowing) become more prominent and adults tend to present with symptoms of dysphagia and strictures.

It is common for patients with this EO to have a history of other allergic symptoms such as hayfever or food allergy You may also have a family history of EO or other allergic conditions.

EO produces intermittent symptoms and usually follows a chronic and relapsing course. You may gain some symptomatic relief from acid-blocking medications but these do not alter the changes in the oesophagus.

Symptoms

If you experience any of the following symptoms you may suffer from EO:

• Abdominal pain;
• Nausea;
• Vomiting;
• Heartburn;
• Chest pain;
• Dysphagia: This is the classic symptoms in adults. An unpleasant sensation of food sticking in the oesophagus after swallowing is highly suggestive of EO and should prompt you to see your doctor for further testing. This symptom develops because the oesophagus loses its ability to stretch and accommodate solid pieces of food.

When you present to your doctor, they will take a careful history of your symptoms as well as question you about other allergic disorders (such as hayfever, asthma or eczema) and family history of other relatives having similar or related disorders. An allergic history in yourself or family may increase the likelihood of a diagnosis of EO.

Children

Infants can present with similar symptoms of GORD, usually abdominal pain, nausea and/or vomiting. They also tend to present with additional features including coughing, feeding difficulties, feeding refusal, poor weight gain and failure to thrive. If your child develops these symptoms it is important for you to see your doctor.

Clinical Examination

EO cannot be diagnosed on clinical examination alone. However your doctor will still need to examine you to rule out other causes of your symptoms. In children there may also be signs of poor growth that need to be checked for on examination.

How is it Diagnosed

The most important investigation for EO is upper gastrointestinal endoscopy and biopsy. Multiple samples of oesophageal tissue must be taken and examined under the microscope looking for an eosinophilic infiltrate. Just looking down the oesophagus is insufficient as approximately one third of patients with EO will have a normal appearing oesophagus. If EO is suspected, biopsies must always be taken.

Your doctor may also order some other additional tests such as skin prick testing (SPT), RAST testing and serum levels of IgE and eosinophils. These can be helpful in deciding whether you have atopic (allergic) tendencies but their predictive value in diagnosing EO is not known. The can be useful for identifying causative food allergens so these can be avoided in the future.

Prognosis

The long-term prognosis for EO is largely unknown. Occasionally infants and young children with food protein-induced EO can grow out of the condition as their immune system and tolerance changes. In the majority of cases however, EO follows a chronic and relapsing course.

Unlike chronic GORD or Barrett’s oesophagus, EO is not associated with an increased risk of malignancy (namely adenocarcinoma of the oesophagus). However, chronic inflammation can cause other complications including obstructive dysphagia (difficulty swallowing), strictures or persistent oesophageal narrowing.

Treatment

Treatment for EO remains controversial as there have been few studies evaluating the risks and benefits of treatment options. However, the following treatments may be used if you suffer from EO.

Dietary therapy

In infants and children there is strong evidence that food allergy is involved in the pathogenesis of EO. Thus removing offending agents form the diet should theoretically treat disease. Doctors may use elimination diets where your child is required to avoid typical causative agents such as soy, wheat or eggs or agents identified by skin-prick and RAST testing.

Alternatively, elemental diets such as formulas containing only amino-acids (without any proteins to act as allergens) may be used. Your doctor may treat your child with an elemental diet for several months and then slowly introduce different foods to identify the causative agent.

In adults, the evidence for dietary therapy is less well understood. Elemental diets tend to be poorly tolerated in older children and adults for periods longer than a few weeks. In addition, it can be difficult to identify single causative agents so dietary therapy can be impractical.

Medications

Both adults and children may benefit from treatment with anti-inflammatory medications. A common agent used is swallowed (not inhaled) fluticasone. This medication comes in a puffer similar to asthma medications but is used without a spacer so the majority of the medication is deposited in the throat. Swallowing of this steroid drug helps treat the inflammation of the oesophagus.

In very severe cases, systemic steroids may be needed but these are associated with several side effects such as weight gain, high blood pressure, easy bruising and thrush. A number of other medications may be used including mast celll stabilisers and leukotriene receptor antagonists. Most patients will also be given concurrent proton-pump-inhibitors to treat any associated reflux.

Oesophageal dilatation

This is the main treatment used in adults with EO. Remember that most adults present with dysphagia due to strictures or narrowing in the oesophagus. There are various procedures used to carefully dilate the oesophagus to allow better passage of food. These can be done using endoscopes, long and flexible dilators inserted through the mouth or using balloon devices inserted through the endoscope.

Oesophageal dilation is a painful procedure and can cause serious side effects such as mucosal tears or perforation. You should discuss with your doctor whether this treatment is suitable for you. It may be preferable to have a trial of medications and consider this treatment if medication fails.

Oesophageal dilation is rarely performed in children unless they have fixed and severe strictures.

Supportive care

ausEE Inc. is a registered Australian charity dedicated to providing support and information to anyone diagnosed with or caring for someone with an eosinophilic gastrointestinal disorder (EGID), including eosinophilic oesophagitis. For more information, see ausEE Inc.

References

1. Kakakios A, Heine R. Eosinophilic oesophagitis. Med J Aust. 2006;185(7):401. [Full text]
2. Liacouras CA. Eosinophilic esophagitis: Treatment in 2005. Curr Opin Gastroenterol. 2006;22(2):147-52. [Abstract]
3. Liacouras CA, Ruchelli E. Eosinophilic esophagitis. Curr Opin Pediatr. 2004;16(5):560-6. [Abstract]
4. Owyang C, Longo D. Hot topic: Eosinophilic esophagitis. In: Braunwald E, Fauci AS, Kasper DL, et al. Harrison’s Principles of Internal Medicine (16th edition). New York: McGraw-Hill Publishing; 2005. [Book]
5. Rudolph C. Eosinophilic esophagitis. In: Rudolph CD, Rudolph AM, Hostetter MK, et al. Rudolph’s Pediatrics (21st edition). New York, NY: McGraw-Hill; 2003. [Book]