The fifth is Cogan’s syndrome, which consists of a sudden onset of interstitial keratitis and severe vestibuloauditory dysfunction. This syndrome responds to high-dose steroids, but patients may eventually become resistant to the treatment.
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December 2007The sixth category consists of AIED-like causes of hearing loss. Here, an idiopathic rapidly progressing bilateral sensorineural hearing loss that can lead to deafness often occurs in young people and consists of severe ear pain, pressure, and tinnitus. This condition is not responsive to immunosuppressive drugs, including steroids.
Defining Autoimmune Conditions
However, there are no perfect ways of diagnosing AIED. Indeed, according to Dr. Rauch, there is still controversy over the very nature of some types of AIED. There are strict criteria for confirming that a disease is autoimmune. These criteria have not been met for the condition commonly called AIED. It would be more accurate, he said, to call it immune-mediated inner ear disease (IMIED).
This doesn’t mean hearing isn’t affected by autoimmune disease. There are systemic autoimmune diseases, such as lupus, rheumatoid arthritis, ulcerative colitis and others that affect various organs, and occasionally affect the ear. So, yes, we do sometimes see hearing loss in a patient with one of these diseases. But it’s not common, Dr. Rauch said.
Statistics on the rates of AIED are so elusive that experts can only say the condition is rare.
The general opinion in otolaryngology is that there is an autoimmune component to idiopathic, rapidly progressive hearing loss where no other organs are involved. The idea was initially proposed in 1979 when it was found that even though an actual autoimmune disease could not be detected, patients responded to steroid treatment.
The hypothesis has been that somehow it’s immune-mediated. But no one has ever proven that it’s autoimmune, Dr. Rauch said. There have been no consistent autoimmune markers for the condition found in blood, and no definitive evidence from imaging or other tests either.
Of course, there are always exceptions to the rule, and about 15% of cases have some sort of abnormal blood work indicating immune dysregulation. Still, that means 85 percent of the time everything is normal, but the patient’s hearing is dropping rapidly, Dr. Rauch said.
What’s a Physician to Do?
So, how does an otolaryngologist handle a condition that has elusive causes? First, Dr. Rauch suggests not plunging straight into steroid treatment. The reason is that steroid doses are high, are administered for a lengthy period of time, and patients almost invariably suffer side effects. Instead, he suggests following the patient closely for at least a couple of months.