Hearing Loss Related to Autoimmune Inner Ear Disease

Making a hearing test
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Autoimmune inner ear disease is a rare condition that results in a rapid decline in your ability to hear and sometimes symptoms such as dizziness or loss of balance.

What Is Inner Ear Autoimmune Disease and What Causes It?

Autoimmune diseases that affect the inner ear are not all well understood, however, they generally involve components of the immune system (immune cells or antibodies) which for unknown reasons begin to attack the structures that make up the inner ear.

There are several theories about how this happens but this usually occurs in relation to another co-existing autoimmune disorder such as:

Some infectious illnesses have also been associated with autoimmune hearing loss. These include:

  • Lyme disease
  • Syphilis

These illnesses are thought to be associated with increased antibody production and the subsequent attack of the inner ear by those antibodies. Other possible causes or related conditions include:

  • Post-traumatic hydrops (a rare condition that occurs after a head injury)
  • Surgical trauma or temporal bone trauma
  • Meniere's disease

Hearing loss caused by autoimmune disease is a relatively rare cause of hearing loss accounting for approximately 1 percent of cases.

Symptoms of Autoimmune Inner Ear Disease

The most characteristic symptom of autoimmune inner ear disease is sudden hearing loss which usually occurs in both ears (bilaterally).

This rapid hearing loss is usually classified as sensorineural and often accompanied by vestibular symptoms such as dizziness or loss of balance. The hearing loss usually occurs over a period of a few months.

Diagnosing Autoimmune Inner Ear Disease

If you have symptoms of autoimmune inner ear disease your doctor may use a combination of several tests to help confirm this diagnosis. Here are some of the tests your doctor may choose to order:

  • Blood tests to help confirm or rule out an underlying autoimmune disorder (ANA, erythrocyte sedimentation rate, rheumatoid factor, human leukocyte antigens, C-reactive protein).
  • Other blood tests may include: anti-cochlear antibody test, lymphocyte transformation assay, Lyme titer.
  • Various hearing tests including: audiometry, ABR, otoacoustic emission testing, ECOG (electrocochleography).
  • Your doctor may also choose to try an immunosuppressive medication or a corticosteroid and see if you respond to it. A positive response would help to confirm a diagnosis of autoimmune inner ear disease. However, if you don't respond to the medication it does not necessarily mean that you do not have autoimmune inner ear disease.
  • Rotary chair test: This test helps to determine if dizziness or balance problems are stemming from the vestibular system or another part of the body.

    None of the tests listed above are specific for autoimmune inner ear disease but are used to help rule out or confirm associated conditions. A diagnosis is based on a combination of your symptoms, medical history, the doctor's findings during a physical exam as well as any relevant test results.

    Treating Autoimmune Inner Ear Disease

    Often the first line of treatment is a course of oral steroid medication such as prednisone, dexamethasone, or even aldosterone. They are usually used for a period of about 1 month. Steroids are usually not used in individuals with diabetes, peptic ulcer disease, glaucoma, or high blood pressure.

    Steroids are effective about 60 percent of the time. Steroids should never be discontinued abruptly, but rather slowly tapered.

    Oral steroids can cause significant side effects in some people. For this reason your doctor may choose to put the steroids directly into your inner ear (this method of administering the medication is called transtympanic). This involves a small surgical incision being made in the ear drum (called a myringotomy) which can often be done with a local anesthetic or, if necessary, at a hospital or surgical center under general anesthesia. A tympanostomy tube is usually placed to keep the incision open so that treatment can be continued for a period of time. The procedure is relatively simple and doesn't generally cause much pain. Once the tube is removed the incision will heal on its own pretty quickly.

    If you are not a candidate for steroid therapy or if steroid therapy does not work for you, your doctor may choose another medication.

    Cytotoxic medications such as methotrexate and cyclophosphamide may be effective in treating autoimmune inner ear disease when steroids fail or are not an option, however side effects may limit their use. Methotrexate is usually used because it is associated with less side effects than other cytotoxic drugs and when side effects do occur they are usually mild and reversible.

    Side effects of methotrexate and cyclophosphamide may include: anemia, thrombocytopenia, kidney or liver toxicity, infertility or bone marrow suppression. While taking these medications, your health should be closely monitored by a physician and routine blood tests to monitor your kidney or liver function may be necessary. Treatment with methotrexate has a success rate of approximately 69 percent.

    Other medications your doctor may choose to try include:

    • Etanercept (a tumor-necrosis factor antagonist)
    • N-acetylcysteine

    Research proving the effectiveness of these medications is very limited so your doctor may only choose to try them if other treatments have failed.

    Another possible treatment that needs to be further researched is plasmapheresis. Plasmapheresis is the process of filtering a person's blood to remove the components of the immune system which are thought to be attacking the inner ear (antigen, antibodies, etc). The substances of the immune system that are removed are replaced with normal saline or a protein called albumin (or both). This treatment can be expensive and is unlikely to be used as a first line treatment.

    Regardless of the treatment used, research has shown that the sooner treatment is started the more effective it is likely to be. For this reason you should see a doctor immediately if you have any symptoms of autoimmune inner ear disease.

    Sources:

    Autoimmune Inner Ear Disease (AIED). American Hearing Research Foundation website. http://american-hearing.org/disorders/autoimmune-inner-ear-disease-aied/. Updated October 2012. Accessed June 17, 2017.

    Autoimmune Inner Ear Diseases (AIED's): Autoimmune Diseases with Audio-Vestibular Involvement. Audiology Online website. http://www.audiologyonline.com/articles/autoimmune-inner-ear-disease-aieds-1160.  Updated August 2002. Accessed June 17, 2017.

    Autoimmune Disease of the Inner Ear Treatment & Management. Medscape website. http://emedicine.medscape.com/article/857511-treatment. Updated December 2016. Accessed June 17, 2017.

    Rotary Chair Testing. Medscape website. http://emedicine.medscape.com/article/1832765-overview. Updated February 2016. Accessed June 17, 2017.

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