Reference
Glossary
The working vocabulary of autoimmune inner ear disease. Inline dotted terms throughout the chapter link here.
- 68-kDa protein / HSP-70 · heat shock protein 70
- A stress-induced chaperone proposed as the target of the 68-kDa antibody described by Moscicki — historically the best-known AIED serological marker, but never standardised and now considered investigational.
- ANCA
- Antineutrophil cytoplasmic antibodies — serological markers of vasculitides such as GPA; their detection supports a vasculitic cause of audiovestibular disease.
- Antiphospholipid syndrome (APS)
- A prothrombotic autoimmune disorder (anticardiolipin / anti-β2-glycoprotein-I antibodies) that can cause inner-ear microthrombosis and recurrent or sudden hearing loss and vertigo.
- Autoimmune inner ear disease (AIED) · AIED · immune-mediated hearing loss
- An aberrant immune response against inner-ear antigens causing rapidly progressive, often bilateral sensorineural hearing loss with vestibular symptoms. Rare (<1% of SNHL) but important because it is steroid-responsive if caught early.
- Blood–labyrinth barrier
- The barrier that keeps the inner ear immune-privileged by excluding circulating immune cells and large molecules. Its breakdown lets immune components reach inner-ear antigens and initiate AIED.
- Cochlear implantation
- Auditory rehabilitation for bilateral severe-to-profound SNHL that fails amplification; outcomes in AIED are generally favourable once disease is stable and the cochlea is patent.
- Cochlin
- A major non-collagenous extracellular-matrix protein of the cochlea and vestibule; anti-cochlin antibodies have been reported in some patients with immune-mediated hearing loss.
- Cogan's syndrome
- An autoimmune vasculitis combining interstitial keratitis with audiovestibular dysfunction (SNHL, vertigo, tinnitus), often bilateral and progressive; may include large-vessel vasculitis such as aortitis.
- Complement / membrane-attack complex · C5b-9 · MAC
- A cascade that, once the blood–labyrinth barrier is breached, forms the membrane-attack complex (C5b-9) and directly lyses cochlear and vestibular cells.
- Granulomatosis with polyangiitis (GPA) · Wegener's granulomatosis · ANCA vasculitis
- An ANCA-associated granulomatous vasculitis of the airways and kidneys that can cause otitis media, SNHL and progressive vestibular symptoms, with bony destruction if untreated.
- Immune complex
- Antibody–antigen aggregates that can lodge in the stria vascularis microvasculature, obstructing capillaries and causing ischaemic inner-ear injury — a prominent mechanism in lupus.
- Intratympanic corticosteroid
- Steroid (commonly dexamethasone) delivered across the round-window membrane, giving high local concentration with low systemic toxicity — an alternative or adjunct when systemic steroids are unsuitable.
- Methotrexate
- The best-studied steroid-sparing immunosuppressant in AIED, used in weekly low doses to maintain remission and reduce corticosteroid dependency.
- Sensorineural hearing loss (SNHL) · SNHL
- Hearing loss from cochlear or cochlear-nerve dysfunction. In AIED it is characteristically bilateral and rapidly progressive over weeks to months — the hallmark feature.
- Steroid responsiveness
- Improvement in hearing and vertigo with corticosteroids — both a diagnostic clue and a treatment goal in AIED, since the diagnosis lacks a confirmatory test.
- Vestibular evoked myogenic potentials (VEMP) · cVEMP · oVEMP
- Reflex tests of otolith (saccular/utricular) and central vestibular conduction. Abnormal or absent responses in AIED indicate otolith end-organ involvement.
- Video head impulse test (vHIT)
- A canal-specific test of the vestibulo-ocular reflex; reduced VOR gain or corrective saccades in AIED indicate semicircular-canal dysfunction, often horizontal.