Autoimmune diseases are those resulting from an overly aggressive response of the immune system to a substance, providing inflammation in the body. In some cases, the immune system will attack the ear itself, producing symptoms such as a rapidly progressive sensorineural hearing loss, dizziness, chronic infections, and drainage. The most common autoimmune disease is allergy.
Allergy is a term used to describe an over-reaction of the body to a substance in the environment that is normally harmless to most people. This substance is called an allergen, and one can be exposed to it in several ways. It may be breathed into the respiratory system, eaten, or touched by the skin to cause symptoms. Many people inherit a tendency to develop allergies. Autoimmune disease is allergy.
Symptoms and/or Signs of Allergy
A stuffy nose, runny nose, polyps (growths) in the nose, itching and puffy eyes, frequent sore throats, asthma, skin rashes, and behavioral problems such as hyperactivity in children may be symptoms of allergy. Symptoms may occur in almost all systems of the body, including ears.
Chronic itching or frequent infections and drainage of the ear canal may be due to allergy.
Repeated ear infections and long-standing fluid behind the ear are often due to allergy. Both of these are more common in children. Swelling of the Eustachian tube may be due to allergy, and result in ear fullness or cracking in the absence of fluid.
Dizziness, ear fullness and pressure, tinnitus (head noise), and sensorineural (nerve) hearing loss may be due to allergy. Meniere’s Disease in one or both ears may sometimes be caused by allergies.
Types of Allergies
The symptoms of allergy may be produced by inhalants (airborne), food, and/or contact allergens. Reactions of the immune system (autoimmune disease) may also cause symptoms.
Symptoms of inhalant allergy are caused by reactions to allergens that enter the body via the respiratory tract. They may develop with recurrent or prolonged exposure to the allergen. These can be pollens, dust, molds, animal dander, or other substances breathed in through the nose.
Symptoms of inhalant allergy may be year-round or seasonal. Hay fever is a form of inhalant allergy due to weed pollens, which is worst in the late summer and fall.
When the nose or lungs are exposed to repeated contact with allergens, the immune system of allergic patients makes a high level of blood protein or antibody called immunoglobulin E (IgE). The IgE attaches to special allergic cells, called mast cells, found throughout the body. When the allergen enters the respiratory tract, a change occurs in the mast cell’s outer membrane, causing the cell to release substances called mediators, which produce allergic symptoms. One of these mediators is called histamine; it causes congestion and swelling of tissue. That is why an antihistamine is frequently prescribed for allergy symptoms.
Often, common foods that are eaten frequently are the ones that cause symptoms of food allergy. Allergens taken into the digestive track such as wheat, corn, eggs, yeast, nuts, shellfish and dairy products can cause allergic symptoms such as nasal congestion, hives, or ear infections.
Non-food substances that are ingested may cause similar symptoms. These would include medicines such as penicillin or sulfa, or chemicals such as food preservatives.
Contact Dermatitis (skin rash)
Contact dermatitis is a rash or swelling caused by a direct contact of an allergen with the skin. Poison ivy, nickel earrings, wool shirts or certain eardrops may stimulate a cell called the T lymphocyte to release allergic mediators, which affect the skin. The rash may last many weeks or months after exposure.
Autoimmune Inner Ear Disease (AIED)
Autoimmune hearing loss is believed to be caused by the body’s immune system attacking the inner ear and damaging the hearing nerve. Autoimmune disease occurs when the body produces an immunological or inflammatory reaction to itself, instead of reacting to an external substance. No one knows why this occurs. Some patients have signs of other diseases caused by an overly active immune system – arthritis, skin rash, allergy, etc. Symptoms of inner ear involvement may include fluctuating (changing) hearing, often with dizziness and ear fullness, Meniere’s Disease, or a sudden or rapidly progressive loss of hearing.
Antihistamines and Nonspecific Treatment
Mild allergic symptoms require no specific test for diagnosis, and can be well controlled with some combination of antihistamines, prescription nasal sprays, and avoidance of known allergens. Side effects of antihistamines include dry mouth and drowsiness.
More severe or chronic allergic symptoms and those not controlled by medication – especially those involving the inner ear – may require tests to identify the specific allergens.
Diagnostic of Specific Allergens
Specific allergens may be diagnosed by skin testing, blood tests, or a challenge test. Blood tests are also used in the diagnosis of autoimmune inner ear disease.
Skin Testing For Inhalant Allergies
There is no known medical or surgical treatment that will restore hearing in sensorineural hearing impairment. Treatment consists of rehabilitation through the use of hearing aids and special training. Children with profound sensorineural hearing loss can be treated with a cochlear implant.
In Vitro Test (blood test)
An in-vitro test (sometimes called a RAST test) is a blood test sometimes used to diagnose food and inhalant allergies. It measures antibodies (such as IgE) to specific allergens, and may be used to determine your sensitivity to inhalants and some forms of food allergy.
Challenge Test For Food Allergies
Skin testing may help to diagnose food allergies. Many patients crave foods to which they are allergic, and the doctor may take a food history from you to identify some of these. An in-vitro test may be ordered, or a challenge test may be necessary to determine what foods may cause symptoms after they have been eaten.
Foods to be tested may be either eaten or injected in a purified form. When the food has been absorbed, the allergic patient may develop common symptoms of allergy such as nasal stuffiness, a change in hearing, or ringing in the ears.
Blood test for Autoimmune Inner Ear Disease
Autoimmune inner ear disease is usually diagnosed on the basis of a bilateral, rapidly progressive sensorineural hearing loss. Special blood tests may show whether or not the immune system is overly active against the inner ear or other areas. The doctor may sometimes detect evidence of involvement in other parts of the body, such as the kidney or skin.
Treatment of Allergy
The type of treatment for allergy depends on the underlying cause. It may involve desensitization (allergy shots), avoidance, or medications. At times, the underlying cause can be controlled but it is necessary to do something surgical to eliminate the problem that has resulted from the allergy
If the doctor suggests desensitization therapy for inhalant allergies, you will be given injections once or twice a week. These injections contain the allergens to which you are sensitive. They stimulate the production of a protective substance called blocking antibody to help prevent allergic symptoms. You will sometimes need to have the skin tests re-checked to adjust the allergy dose.
You will be asked to eliminate, temporarily, the foods to which you are allergic. This will allow your body to develop tolerances to those foods. You will also be asked to rotate (vary) the other foods in your diet to prevent new food allergies from developing.
The doctor will try to determine what substances may be causing your symptoms and have you avoid the allergens. An anti-inflammatory medicine called a steroid may also be prescribed in a pill, cream, or drop form to help decrease the inflammation.
Autoimmune Hearing Loss
The doctor may want to prescribe an anti-inflammatory medicine called a steroid to suppress or slow down an overly active immune system. It may be necessary to prescribe other medicines to help regulate the immune system, or it may be recommended that you be tested for allergies. Affected patients may have improved or stabilized hearing and balance after treatment.
Ear symptoms due to allergy, such as fluid in the middle ear space, can be treated by the surgical placement of a ventilation tube in the eardrum. Surgery to control dizziness is necessary at times, even though the underlying problem started as a result of an allergy. Following surgery, it may be necessary to treat the underlying allergic problem itself to prevent the symptoms from recurring.