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Autoimmune Inner Ear
Disease (AIED)
Disease/Disorder Name:
Autoimmune Inner Ear Disease (AIED),
Cochlea Autoimmune Disorder (CAD)
ICD-9 Technical Description: Acoustic
neuritis: Degeneration of acoustic or eighth nerve/
NOS Disorder of acoustic or eighth nerve
ICD-9 Code Family:
388.5
ICD-9 Description:
Hearing Loss due to the
body's immune system attacking the cells of the
inner ear..
Introduction to AIED
Autoimmune Inner Ear Disease (AIED) is a disorder of the body's immune system
that attacks the cells of the nerves of the inner ear with antibodies, thinking
these cells are somehow alien to the body and need to be destroyed. AIED is an
allergy of the body's immune system to a part of the body itself.
Known Factors for AIED
AIED is Inherited
Usually other family members
will often have the same or similar autoimmune disorders.
Research indicates that the
probability of developing an
autoimmune disease is determined by a dominant genetic trait that is very common
(20% of the population i.e. about 20% of any population have some kind of
autoimmune disorder). Several
different autoimmune diseases often occur within the same family.
Genetic
predisposition to AIED alone does not cause it to develop. Other
factors need to be present as well in order to initiate the disease process. Evidence suggests that
environmental factors such as bacteria, viruses, toxins and some
drugs may play a role in triggering an autoimmune response in someone who
already has a genetic (inherited) predisposition to autoimmune reactions.
Researchers think that the inflammation initiated by these agents, whether toxic
or infectious, somehow provokes in the body a "sensitization" (autoimmune
reaction) to the involved tissues.
Instances of Meniere's Disease may be caused by AIED
Meniere's disease
and AIED appear to be closely intertwined and it appears that different genetic
factors may be associated with this combination. For
example, in one study, 44% of patients with Meniere’s had one particular genetic
trait as compared to only 7% of the controls. One
study indicated that immune system dysfunction was responsible for 16% of people
with bilateral Meniere's disease and 6% of all people with any variety of
Meniere's disease. In another study, 96% of the patients with Meniere's disease
had elevated levels of circulating immune complexes, compared to just 20% of the
controls. In yet another study, specific immune system antibodies were detected
in 47% of people with Meniere's disease. These studies suggest that more
incidents of Meniere’s
disease may be caused by immune dysfunction than is presently generally thought.
In fact, most researchers now feel that many people with Meniere's symptoms in
both ears have the autoimmune response as the underlying cause.
Other Known Indicators for AIED
Many people with AIED have balance problems.
These symptoms can include vertigo, dizziness, disequilibrium, and ataxia (staggering
movement when walking). Up to 50% of people with AIED have tinnitus (ringing,
roaring, hissing, etc. in their ears) and/or a feeling of fullness in their
ears.
AIED affects women more than men. In fact up to 75% of all autoimmune diseases occur in women
probably due to hormonal influences, and women with two or more autoimmune
disorders are more prevalent that men, with most autoimmune disorders occurring
in young adults and middle age people.
How AIED is Diagnosed
There are specific primary or secondary tests for the presence of the antigen (s)
that indicate AIED. There are general allergy tests that will allow a physician to narrow down
the diagnosis of whatever autoimmune disorders you may have (differential
diagnoses and rule in/rule out procedures). Doctors try to diagnose AIED based
on family history, medical history, findings of physical examination, blood tests, and the
results of hearing and balance tests.
As part of the differential rule in/rule out procedures, the following are
indicators for AIED:
Family members have autoimmune disorders.
The patient has one or more autoimmune disorders.
With AIED, hearing loss progresses slowly
and is often unnoticeable in its early stages as opposed to a sudden hearing
loss.
Hearing loss may fluctuate then stabilize at a certain level in a number of
deteriorating steps.
Treatment for AIEDS
There is no cure for AIEDS - only treatment to slow or stop the body from
attacking what few inner ear nerve cells are left. Why? No one has figured out
how to filter every single antigen cell from the body so the body's immune
response will not attack its own tissues.
It has been found that people with
autoimmune disorders will often have allergies and when treated for those
allergies they often show improvement in AIED indicators such as vertigo and other Meniere’s symptoms,
suggesting an association between Immunoglobulin E (IgE) disease and inner ear problems.
If left alone, a person with AIEDS would probably become profoundly deaf as the body continues to attack the
nerve cells. The only treatment that doctor's have tried is to try steroids to suppress
the body's inflammation/immune response. Some
of the more common drugs prescribed are; Prednisone (or Hydrocortisone), Methotrexate, and
Cyclophosphamide, although with no clinical
trials at this time, doctors really don't know what strength to prescribe and
for how long.
One of the chief ways doctors confirm their diagnosis of AIED is if there is a
positive response the to
steroid treatment i.e. hearing is stabilized or improved, it confirms their
diagnosis that it must have been AIED (Not very scientific but the best that can
be done under the circumstances- *author's comments)
Cautions on Expectations
If drug treatment is decided upon, then treatment should begin as soon as the
diagnosis is positive in order to stop further deterioration of the nerve
cells. However, aggressive drug treatment might not work, and there are
many side effects to heavy doses. And the hearing loss may still progress. Some people respond positively to treatment whereas others do not.
Overall, steroid response rates are approximately 60%. Success is defined as
a hearing improvement of just 10-15 dB, or a "significant" improvement in
discrimination scores. For a severe loss, this is not all that great an
improvement, but at least the hearing loss isn’t progressing any more.
Descriptions of other autoimmune disorders
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