Autoimmune sensorineural hearing loss: Clinical course and treatment outcome

Sensorineural Hearing Loss in Sjögren’s Syndrome

Sjögren’s syndrome is a chronic autoimmune disease characterized by systemic dysfunction of exocrine glands, mainly the salivary and lachrymal glands. Sjögren’s syndrome consists of two forms: primary Sjögren’s syndrome, which is characterized by dry eyes and dry mouth without autoimmune diseases; and secondary Sjögren’s syndrome, which is characterized by symptoms associated with other autoimmune diseases, such as systemic lupus erythematosus. Disease severities vary considerably from mild glandular dryness to severe glandular involvement with numerous extraglandular and systemic features. Sensorineural hearing loss is sometimes observed in both primary and secondary Sjögren’s syndrome. This review article consists of (1) Pathology of Sjögren’s syndrome, (2) Clinical manifestation of Sjögren’s syndrome, (3) Autoimmune inner ear disease, (4) Histoanatomical features of the inner ear, (5) Immunological characteristics of the inner ear, (6) Pathophysiology of autoimmune inner ear disease, (7) Treatment for sensorineural hearing loss in Sjögren’s syndrome, and (8) Future direction. Finally, we introduce a recently developed disease model of salivary gland inflammation and discuss future expectations for the treatment of sensorineural hearing loss in Sjögren’s syndrome.

LCCL peptide cleavage after noise exposure exacerbates hearing loss and is associated with the monocyte infiltration in the cochlea

Acoustic trauma induces an inflammatory response in the cochlea, resulting in debilitating hearing function. Clinically, amelioration of inflammation substantially prevents noise-induced hearing loss. The Limulus factor C, Cochlin, and Lgl1 (LCCL) peptide plays an important role in innate immunity during bacteria-induced inflammation in the cochlea. We aimed to investigate the LCCL-induced innate immune response to noise exposure and its impact on hearing function.

METHODS

We used Coch (encodes cochlin harboring LCCL peptide) knock-out and p.G88E knock-in mice to compare the immune responses before and after noise exposure. We explored their hearing function and hair cell degeneration. Moreover, we investigated distinct characteristics of immune responses upon noise exposure using flow cytometry and RNA sequencing.

RESULTS

One day after noise exposure, the LCCL peptide cleaved from cochlin increased over time in the perilymph space. Both Coch^-/- and Coch^G88E/G88E mutant mice revealed more preserved hearing following acoustic trauma compared to wild-type mice. The outer hair cells were more preserved in Coch^-/- than in wild-type mice upon noise exposure. The RNA sequencing data demonstrated significantly upregulated cell migration gene ontology in wild-type mice than in Coch^-/- mice following noise exposure, indicating that the infiltration of immune cells was dependent on cochlin. Notably, infiltrated monocytes from blood (C11b⁺/Ly6G^-/Ly6C⁺) were remarkably higher in wild-type mice than in Coch^-/- mice at 1 day after noise exposure.

CONCLUSIONS

Noise-induced hearing loss was attributed to over-stimulated cochlin, and led to the cleavage and secretion of LCCL peptide in the cochlea. The LCCL peptide recruited more monocytes from the blood vessels upon noise stimulation, thus highlighting a novel therapeutic target for noise-induced hearing loss.

Audiological Patterns in Patients with Autoimmune Hearing Loss

INTRODUCTION

The aim of this study was to illustrate clinical and audiological patterns of hearing impairment in patients with autoimmune hearing loss (AIHL).

METHODS

Fifty-three patients with AIHL were retrospectively recruited, and a tapering schema of steroid treatment was administered in all these patients. The diagnosis of AIHL was essentially based on clinical symptoms, such as recurrent, sudden (sensorineural hearing loss [SSHL]), fluctuating, or quickly progressing (<12 months) SSHL (uni-/bilateral), in association with the coexistence of autoimmune diseases, high antinuclear antibodies (ANA) and the presence of human leukocyte antigen (HLA) B27, B35, B51, C04, and C07. Logistic regression analysis was applied to correlate the clinical data and laboratory features of AIHL with final outcomes.

RESULTS

The onset of AIHL was mainly progressive (49%), followed by SSHL (39.6%) or fluctuating (11.3%). The pure-tone audiogram showed more commonly a downsloping pattern (42.6% of ears), but also an upsloping, flat, cookie-bite, or inverse cookie-bite shape. Bilateral progressive AIHL was more frequently simultaneous (23 patients) than heterochronous (4 patients). Nineteen patients (35.8%) showed a favorable response to steroid therapy. The presence of recurrent, bilateral SSHL versus recurrent, unilateral SSHL had statistically negative effect on hearing recovery (OR = 0.042, p < 0.05). The heterochronous bilateral SSHL may have better prognosis than simultaneous bilateral SSHL (OR = 10.000, p = 0.099). The gender, age, concomitant autoimmune disease, high ANA, HLA alleles, tinnitus, and vestibular symptoms had no statistical effect on a favorable outcome of AIHL.

CONCLUSIONS

A bilateral, simultaneous, and progressive hearing loss combined with downsloping audiogram occurred more often in patients with AIHL. Bilateral simultaneous SSHL with recurrences represents the worse prognostic form of AIHL.

Long-term (16-26 years) follow-up outcome of steroid therapy in refractory autoimmune sensorineural hearing loss

Autoimmune sensorineural hearing loss (ASHL) is a rare disease of uncertain etiology, with no established treatment strategy. The duration of morbidity is increased in refractory cases; and therefore, the preservation of hearing and the prevention of adverse effects with steroid therapy are serious long term issues to consider. Long-term follow up of patients treated for ASHL was performed retrospectively in order to elucidate the pathogenesis of ASHL, evaluate the consequences of steroid therapy, and determine a promising treatment course. The cohort in this study consists of four female patients with refractory ASHL that were followed for 16-26 years. Three patients already had profound deafness on one side, probably due to ASHL, before the initiation of steroid treatment. ASHL was managed with steroid administration and the hearing was evaluated through regular audiometric tests (173-212 times). The relationship between pure tone threshold average and steroid dose was reviewed over a long-term follow-up period for each patient. During follow-up, hearing deficit progressed rapidly several times in all patients, as did responsiveness to steroid therapy. Long-term high-dose steroid therapy was not required for hearing maintenance. Hearing thresholds were nearly maintained in three patients during the 16- to 21- year follow-up, and gradually declined over a 26-year follow-up period in one patient. Considering the progress due to presbycusis, the maintenance of hearing was considered sufficient in all patients. No serious adverse effects were observed in any of the patients. Management of patients affected by ASHL with regular audiometry allowed for hearing maintenance without the morbidity of prolonged steroid therapy. The current observations give insight into the pathogenesis of ASHL pathogenesis and establish an efficient course of treatment.

Human Leukocyte Antigen (HLA) Influence on Prognosis of Autoimmune Hearing Loss

Background: To evaluate the effect of human leukocyte antigen (HLA) on hearing outcome in patients suffering from autoimmune hearing loss (AIHL). Materials and Methods: The diagnosis of AIHL was essentially based on clinical symptoms, such as recurrent, sudden, fluctuating, or quickly progressing (<12 months) sensorineural hearing loss (uni-/bilateral). The molecular typing of HLA alleles was achieved by using polymerase chain reaction procedures. Patients underwent a tapering schema of steroid treatment and audiometric features were recorded. A logistic regression model was used to identify which HLA typing alleles were statistically significant in patients’ response to treatment. Results: Forty patients with AIHL were found to be carriers of HLA B27, B35, B51, C4, C7, and DRB1*04 alleles. No statistically significant influence of HLA B27, B35, B51, C4, C7, DRB1*04 HLA alleles typing was detected for the prognosis of AIHL. In these patients, the onset of AIHL was mainly progressive (53.8%), 29.2% of them had moderate hearing loss, and most of the cases had both bilateral hearing loss (62.5%) and downsloping audiogram (40%). Conclusion: The presence of HLA B27, B35, B51, C4, C7, and DRB1*04 alleles had no significant effect on a favorable outcome of AIHL. However, larger samples of patients are necessary in order to improve the knowledge about the HLA influence on the clinical course of AIHL.

Autoimmune inner ear disease: A systematic review of management

OBJECTIVES

The study systematically reviewed the existing literature on the management of autoimmune inner ear disease (AIED).

STUDY DESIGN

Systematic review.

METHODS

We performed a literature search of Embase, NCBI, Cochrane, and Web of Science databases from April 1990 to April 2020. Inclusion criteria included studies that were retrospective or prospective in nature evaluating the treatment of AIED with audiometric data measuring hearing outcomes during treatment. Hearing improvement was the primary study outcome and improvement in vestibular symptoms was the secondary study outcome.

RESULTS

Sixteen of 412 candidate articles were included in our study. Systemic steroid treatment is most commonly described. Alternative treatment modalities included intratympanic steroid treatment, methotrexate, cyclophosphamide, azathioprine, infliximab, etanercept, adalimumab, golimumab, methylprednisolone, rituximab, and anakinra.

CONCLUSION

Systemic corticosteroids are the first line treatment of AIED. Intratympanic steroids are a potential adjuvant or alternative treatment for patients who cannot tolerate or become refractory to steroid treatment. Steroid nonresponders may benefit from biologic therapy. Alternative treatment modalities including nonsteroidal immunosuppressants and biologics have been studied in small cohorts of patients with varying results. Prospective studies investigating the efficacy of biologic and nonsteroidal therapy are warranted.

LEVEL OF EVIDENCE

2.

Fluctuating Sensorineural Hearing Loss

BACKGROUND

Several otologic conditions can present with fluctuating sensorineural hearing loss, including Ménière's disease, autoimmune inner ear disease, and enlarged vestibular aqueduct. Although these 3 etiologies vary greatly, distinguishing between these conditions at initial presentation can be challenging. Furthermore, initial treatment of these conditions is often similar. In this review, we discuss historical and current perspectives on diagnosis and treatment of these conditions.

SUMMARY

A literature search was performed regarding fluctuating hearing loss, and current treatment of these etiologies of fluctuating hearing loss was summarized. Immediate measures at the onset of acute hearing loss include corticosteroid therapy, while preventative and chronic therapies, which can limit disease severity and frequency, vary based on the specific condition treated. Key Messages: Fluctuating hearing loss can represent a range of pathologies, but the precise etiology may not be clear at initial presentation. Timely treatment and long-term follow-up, along with appropriate diagnostics, are necessary to optimize long-term hearing.

Emerging options in immune-mediated hearing loss

Objective

AIED (autoimmune inner ear disease) is an autoimmune process that leads to the dysfunction of the inner ear, resulting in fluctuating, audiovestibular symptoms. Although the pathogenesis is likely heterogeneous, immune processes within the inner ear ultimately lead to histopathologic changes and sensorineural hearing loss. This review will discuss the latest evidence on treatment options.

Methods

A literature search on articles pertaining to the treatment of autoimmune inner ear disease was performed on PubMed.

Results

Corticosteroid treatment continues to remain as first line therapy for AIED but long-term responsiveness is poor. Cytotoxic chemotherapies can be effective alternatives for steroid nonresponsive patients, but significant side effects may limit their use. Intratympanic steroid injections are beneficial and although there is not enough evidence currently to supplant oral steroid trial they may be a useful adjunct if steroid toxicity is an issue. The efficacy of biologic agents has been variable. Compared to placebo, etanercept does not improve the hearing improvement already attained by steroids alone. However, open pilot studies of other biologic agents show hearing improvements, improvements in tinnitus/aural fullness/vertigo, ability to wean steroid dependency, or benefits in steroid-resistant AIED.

Conclusion

There is currently not enough evidence that alternative treatments supersede the use of initial steroid treatment. Biologic agents and intratympanic steroid injections are relatively well tolerated and should be considered as adjunctive therapy. More studies on the efficacy of various biologics and more studies on the treatment of steroid resistant disease especially after initial benefit are still needed. For those who eventually lose their hearing, cochlear implantation remains as a viable option.

Level of Evidence

expert opinion.

Alteraciones auditivas en artritis reumatoide, lupus eritematoso sistémico y síndrome de Sjögren

Introducción. En la actualidad no hay cifras sobre las personas que padecen artritis reumatoide (AR), lupus eritematoso sistémico (LES) o síndrome de Sjögren (SS) ni información sobre las alteraciones auditivas que puede causar el tratamiento farmacológico utilizado para controlar dichas enfermedades.Objetivo. Evidenciar las posibles afectaciones y alteraciones audiológicas y vestibulares producidas por AR, LES y SS o su tratamiento farmacológico.Materiales y métodos. Se analizaron los hallazgos clínicos de herramientas diagnósticas y procedimientos de prevención e intervención de alteraciones auditivas en artículos de investigación publicados en español, inglés, francés y portugués en bases de datos científicas entre los años 2000 y 2016.Resultados. Se extrajeron 62 artículos de investigación (31 de AR, 5 de LES, 12 de SS, 5 de Hipoacusia inmunomediada, 9 de medicamentos ototóxicos), 1 tesis doctoral sobre AR, 1 tesis doctoral sobre AR y LES y 1 guía de práctica clínica para la detección temprana, diagnóstico y tratamiento de AR. Se evidenció que las pérdidas auditivas con mayor reporte son hipoacusia neurosensorial, lesiones en cadena osicular y vestíbulo-coclear.Conclusiones. Se confirmó la relación entre las lesiones audiológicas y AR, LES y SS, pero aun no es claro el desarrollo de los ototóxicos.

Hearing loss in autoimmune disorders: Prevalence and therapeutic options

The objective of this study was to review our current knowledge relative to the correlation between sensorineural hearing loss (SNHL) and autoimmune diseases, focusing on the prevalence of hearing loss in different pathologies and possible therapeutic approaches. A review of the literature on hearing loss in different forms of autoimmune disease has been carried out, with emphasis on incidence and prevalence of SNHL. Therapeutic protocols have been assessed including both conservative medical and rehabilitative methods. Cochlear implant outcomes have been investigated. The prevalence of hearing loss in autoimmune and immune-mediated inner ear diseases, as referred by case reports or single-center statistics, is widely variable. More difficult is the evaluation of severe/profound SNHL, usually reported in relation to cochlear implantation. Though these patients represent ideal candidates for cochlear implantation, as they become deaf after years of hearing; the associated systemic disease, the specific damage on inner ear structures and the medication taken may influence the result of cochlear implantation. The main problem is the cochlear fibrosis or ossification that has been found to affect 50% of implanted ears in patients suffering from autoimmune and immune-mediated SNHL. Hence, in the presence of severe/profound SNHL earlier implantation may be indicated before post-inflammatory obliterative changes to the cochlea.

Azathioprine reduces the risk of audiometric relapse in immune-mediated hearing loss

INTRODUCTION

Current schemes for treatment of immune-mediated hearing loss with sporadic short-course, low-dose corticosteroids, are insufficient.

METHODS

To determine the role of azathioprine in the control of auditory impairment, a longitudinal, observational, descriptive study was performed with 20 patients treated with azathioprine (1.5-2.5mg/kg/day into two doses) for 1year. The loss of 10dB on two consecutive frequencies or 15dB on an isolated frequency was considered as relapse.

RESULTS

The mean age of the patients was 52.50years (95%CI: 46.91-58.17), half were women. Bilateral affectation was 65%. 75% had organ specific disease and 25% had systemic autoimmune disease. The difference between baseline PTA (46.49dB; DS18.90) and PTA at 12months (45.47dB; DS18.88) did not reach statistical significance (P=.799). There was a moderate positive correlation between female sex and the presence of systemic disease (R=.577). By applying Student's t for paired data, a significant difference (P=.042) was obtained between the PTA in frequencies up to 1000 Hz (PTA125-1000Hz). The relative incidence rate of relapse per year was .52 relapses/year (95%CI: .19-1.14]). The median time to audiometric relapse-free was 9.70months (DS1.03).

CONCLUSIONS

Azathioprine maintains the hearing threshold, decreases the risk of relapse, and slows down the rate at which patients relapse, altering the course of immune-mediated inner ear disease.

Autoimmune inner ear disease preliminary case report: audiometric findings following steroid treatments

PURPOSE

This study examined the audiometric findings following steroid treatment for autoimmune inner ear disease (AIED), which is characterized by bilateral subacute hearing loss, using oral and intratympanic treatment.

METHOD

The charts of 9 patients with AIED who had been seen in the Saint Louis University School of Medicine's clinic between 2004 and 2011 were reviewed, with special focus on audiometric results.

RESULTS

The majority of patients benefited from treatment for AIED. Four patients (6 ears) received intratympanic therapy as part of their treatment.

CONCLUSION

Patients with AIED appeared to benefit from a clinical pathway using a prolonged course of oral steroids, followed by a trial of intratympanic steroids and/or immunosuppresants for refractory cases.

Corticosteroid therapy for hearing and balance disorders

This review addresses the current status of steroid therapies for hearing and vestibular disorders and how certain misconceptions may be undermining the efficacy in restoring normal ear function, both experimentally and clinically. Specific misconceptions addressed are that steroid therapy is not effective, steroid-responsive hearing loss proves an underlying inflammatory problem in the ear, and steroids only have application to the hearing disorders listed below. Glucocorticoid therapy for hearing and balance disorders has been employed for over 60 years. It is recommended in cases of sudden hearing loss, Meniére's disease, immune-mediated hearing loss, and any vestibular dysfunction suspected of having an inflammatory etiology. The predominant steroids employed today are dexamethasone, prednisone, prednisolone, and methylprednisolone. Despite years of use, little is known of the steroid responsive mechanisms in the ear that are influenced by glucocorticoid therapy. Furthermore, meta-analyses and clinical study reviews occasionally question whether steroids offer any benefit at all. Foremost in the minds of clinicians is the immune suppression and anti-inflammatory functions of steroids because of their efficacy for autoimmune hearing loss. However, glucocorticoids have a strong binding affinity for the mineralocorticoid (aldosterone) and glucocorticoid receptors, both of which are prominent in the ear. Because the auditory and vestibular end organs require tightly regulated endolymph and perilymph fluids, this ion homeostasis role of the mineralocorticoid receptor cannot be overlooked in both normal and pathologic functions of the ear. The function of the glucocorticoid receptor is to provide anti-inflammatory and antiapoptotic signals by mediating survival factors.

Spectrum of immune-mediated inner ear disease and cochlear implant results

OBJECTIVES/HYPOTHESIS

To characterize the progression of hearing loss in patients with immune-mediated inner ear disease (IMIED), and to identify disease- and patient-specific factors associated with cochlear implant (CI) performance.

STUDY DESIGN

Retrospective cohort study.

METHODS

Subjects consisted of CI patients suspected to have lost their hearing due to IMIED. The primary dependent variable for functional decline was time to deafness, whereas for CI benefit it was post-CI speech perception scores. Independent variables included presence or absence of systemic autoimmune disease, age at CI, and insertion depth of the cochlear electrode.

RESULTS

A transient favorable response to immunosuppressive therapy was reported in 16 of 26 patients (66.67%). The time to deafness differed between an organ (ear)-specific immune-mediated group, a systemic immune-mediated group including Cogan syndrome and relapsing polychondritis (subgroup A), and a systemic immune-mediated group associated with other autoimmune diseases (subgroup B; P = .001). Disease group (-15.52; P = .04), insertion depth of the CI electrode (40.71; P = .01), and the age at CI (-0.48, P = .05) were associated with speech perception results.

CONCLUSIONS

Triaging IMIED cases based on presence and type of systemic autoimmune disease may aid in selecting a management strategy. Knowledge about the predictors of CI outcome will help clinicians select appropriate patients for CIs. In the setting of significant and irreversible hearing deficit, the restoration of hearing using a cochlear prosthesis may be appropriate earlier rather than later.

Immunosuppressive therapy for autoimmune inner ear disease

Autoimmune inner ear disease (AIED) is a rare disease that is diagnosed after clinical suspicion and response to corticosteroids. AIED manifests as progressive, bilateral, although often asynchronous, sensorineural hearing loss and can be associated with vestibular symptoms. Since its description as a defined disease entity in 1979, the initial mainstay of treatment remains high-dose corticosteroids. Several animal models have been developed to assist in determining efficacy of immunosuppression in AIED, and several clinical studies have also investigated the role of both steroid and steroid-sparing treatments. Here we discuss the basic science and clinical research surrounding the history of immunosuppressive therapy in AIED.

Cochlear implantation in patients with autoimmune inner ear disease including cogan syndrome: a comparison with age- and sex-matched controls

OBJECTIVES/HYPOTHESIS

Evaluate the characteristics and outcomes of patients with autoimmune inner ear disease (AIED) who have undergone cochlear implantation (CI) and compare post-CI performance in AIED to matched controls.

STUDY DESIGN

Retrospective case control study.

METHODS

Study cohort was comprised of 25 adult implantees (AIED [n = 18], Cogan syndrome [n = 7]). The AIED group was defined by rapidly progressive bilateral sensorineural hearing loss leading to unusable hearing within weeks to months. Patients with Cogan syndrome, the archetypal inner ear autoimmune disease, were also examined and used for within-cohort comparison. Clinical and operative records were reviewed. Post-CI performance was assessed using open-set sentence tests. Age- and sex-matched individuals deafened by other postlingual causes were used as controls.

RESULTS

Of 25 patients, 24 had uneventful, full electrode insertions. One AIED patient had partial insertion due to cochlear ossification and did not achieve open-set speech perception post-CI. Mean open-set sentence scores for study patients with uneventful insertions were 92.8%, 97.3%, and 96.4% at 6 months, 1 year, and ≥ 2 years, respectively. Compared to matched controls, patients deafened by autoimmune causes had significantly higher post-CI performance at all postoperative test intervals (P < .05). There was no significant difference in postimplantation performance between Cogan syndrome and AIED patients.

CONCLUSIONS

To our knowledge this was the largest study of cochlear implantation in AIED and Cogan syndrome patients. In our experience, both groups generally attained high levels of post-CI speech perception and performed above average. Cochlear ossification affecting implantation in Cogan syndrome patients was not observed in our series, contrary to some reports.

Murine autoimmune hearing loss mediated by CD4+ T cells specific for β-tubulin

Autoimmune inner ear disease is described as progressive, bilateral although asymmetric, sensorineural hearing loss and can be improved by immunosuppressive therapy. We showed that the inner ear autoantigen β-tubulin is capable of inducing experimental autoimmune hearing loss (EAHL) in mice. Immunization of BALB/c mice with β-tubulin resulted in hair cell loss and hearing loss, effects that were not seen in animals immunized with control peptide. Moreover, the EAHL model showed that β-tubulin responsiveness involved CD4(+) T cells producing IFN-γ, and T cell mediation of EAHL was determined by significantly increased auditory brainstem response after adoptive transfer of β-tubulin-activated CD4(+) T cells into naive BALB/c recipients. The potential mechanisms responsible for the observed pathology of EAHL can be attributed to decreased frequency and impaired suppressive function of regulatory T cells. Our study suggests that EAHL may be a T cell-mediated organ-specific autoimmune disorder of the inner ear.

Systematic screening for nonspecific autoantibodies in idiopathic sensorineural hearing loss: no association with steroid response

OBJECTIVE

An autoimmune pathogenesis has been suggested for idiopathic sensorineural hearing loss (iSHL). Specific tests have been developed to detect inner ear autoantibodies and have been shown to correlate with treatment outcome. However, the disease is rare, and specific tests are not easily available. We aimed to analyze the correlation between positive systemic autoimmune test results and steroid treatment outcome in patients with iSHL.

STUDY DESIGN

Prospective, single-center, open trial.

SETTING

All patients younger than 60 years seen in the ENT department from 1999 to 2007 and fulfilling the criteria for iSHL were tested for systemic autoimmunity.

PATIENTS

Patients were classified into 2 groups, according to the presence or absence of autoimmunity.

INTERVENTION

: Clinical evaluation and audiologic tests.

MAIN OUTCOME MEASURES

The outcomes of steroid treatment were compared between these 2 groups.

RESULTS

Forty-nine patients were included; the mean age at iSHL onset was 36.1 years. Hearing loss was often bilateral (89.8%). Tinnitus and vertigo were present in 75.5% and 51%, respectively. On audiograms, disease severity was correlated with disease duration. Nine patients (18.4%) had positive autoimmune tests: anti-neutrophil cytoplasmic antibody (n = 1), antinuclear antibody (n = 3), rheumatoid factor (n = 3), and antiphospholipid (n = 2). Twenty-five courses of oral steroids were evaluated after 1 month: 52% of cases experienced some improvement. There were no differences in outcome associated with autoimmune status (p = 0.85).

CONCLUSION

The results of this study suggest that positive autoimmune tests in patients with iSHL are not predictive of improvement after a 1-month steroid course. Therefore, systematic screening does not seem to be useful, and specific inner ear autoantibody tests need to be developed.

Low dose combination steroids control autoimmune mouse hearing loss

The severe side effects of glucocorticoids prevent long term management of hearing loss. Alternative steroid treatments that minimize or eliminate these effects would significantly benefit therapeutic control of hearing disorders. A steroid treatment study of autoimmune mouse hearing loss was conducted to determine the efficacy of combining aldosterone and prednisolone at low doses. An assessment also was made of low dose fludrocortisone, a synthetic mineralocorticoid that also has a slight glucocorticoid effect. MRL/MpJ-Fas(lpr) mice were tested for baseline ABR thresholds at 3 months of age and then treated with aldosterone (3.0 μg/kg) or prednisolone (1.0 mg/kg) to determine the lowest effective dose of each. Other mice were given the two steroids in combination at doses of Pred 0.5 mg+Aldo 1.5 μg; Pred 1.0 mg+Aldo 3.0 μg; or Pred 1.5 mg+Aldo 5.0 μg. Mice were retested with ABR at 1 and 2 months to determine the efficacy of the different steroid treatments in controlling hearing loss. Another series of mice were given the synthetic mineralocorticoid fludrocortisone at low (2.8 μg/kg) or high (10 μg/kg) doses and retested at monthly intervals for 3 months. Autoimmune mouse hearing loss developed in untreated controls. This threshold elevation was not prevented by prednisolone at 1 mg/kg or by aldosterone at 3 μg/kg when each was given alone. However, the two steroids combined at these doses effectively controlled hearing loss. The fludrocortisone treatments also were effective at low doses in preventing or reversing the autoimmune mouse hearing loss. This efficacy of combined steroids at low doses suggests the potential for reducing the side effects of glucocorticoids in the therapeutic control of hearing disorders.

Blocking the glucocorticoid receptor with RU-486 does not prevent glucocorticoid control of autoimmune mouse hearing loss

BACKGROUND/AIMS

Glucocorticoids effectively manage autoimmune hearing loss, although the cochlear mechanisms involved are unknown. Previous studies of steroid-responsive hearing loss in autoimmune (lupus) mice showed glucocorticoids and mineralocorticoids were equally effective, suggesting the ion homeostasis functions of glucocorticoids may be as relevant as immunosuppression for control of autoimmune-induced inner ear disease. Therefore, to better characterize the role of the glucocorticoid receptor in autoimmune hearing loss therapy, its function was blocked with the antagonist RU-486 (mifepristone) during glucocorticoid (prednisolone) treatments.

METHODS

Following baseline auditory brainstem response (ABR) thresholds, MRL/MpJ-Fas(lpr) autoimmune mice were implanted with pellets providing combinations of 1.25 mg/kg of RU-486, 4 mg/kg of prednisolone, or their respective placebos. After 1 month, animals were retested with ABR and blood was collected for immune complex analyses.

RESULTS

Mice receiving no prednisolone (placebo + placebo and placebo + RU-486) showed continued declines in hearing. On the other hand, mice receiving prednisolone (prednisolone + placebo and prednisolone + RU-486) had significantly better hearing (p < 0.05) than the non-prednisolone groups. Immune complexes were significantly elevated in the placebo + RU-486 group, suggesting RU-486 effectively blocked glucocorticoid receptor-mediated immune suppression. These results showed that blockage of the glucocorticoid receptor with RU-486 did not prevent prednisolone's effects in the ear, suggesting its ion homeostasis actions via the mineralocorticoid receptor were more relevant in hearing control.

CONCLUSION

The mineralocorticoid receptor-mediated actions of glucocorticoids are potentially relevant in steroid-responsive hearing disorders, implying disrupted cochlear ion transport functions may underlie the vascular problems proposed in some forms of immune-mediated hearing loss.

The autoimmune characteristics of progressive or sudden sensorineural hearing loss

Autoimmune sensorineural hearing loss (ASNHL) is a clinical syndrome that typically produces a bilateral rapidly progressive hearing loss. Autoantibodies and autoreactive T cells have been implicated in the etiopathogenesis of ASNHL. However, the identity of a specific or highly relevant inner-ear self-antigen is still required. In recent years, a role for antiphospholipid antibodies has been also suggested, assuming sudden/progressive hearing loss to be part of the primary antiphospholipid syndrome (APS). In this review, we address the need for specific diagnostic tools in order to establish an autoimmune origin for hearing loss. Moreover, the decision of whether anti-inflammatory drugs or anti-coagulation should be given is also discussed.

Cogan's syndrome: present and future directions

Cogan's syndrome, typified by the combination of interstitial keratitis and immune-mediated sensorineural hearing loss, is a rare condition, and commonly associated with a diagnostic delay. Using a standard search protocol, we review the literature to date, focusing on a number of key areas pertaining to diagnosis, presentation and treatment. Using a case illustration of atypical disease which led to fulminant aortic regurgitation, we highlight the need for continued and collaborative research in order to identify negative prognostic factors and thus tailor therapeutic regimens. Atypical Cogan's syndrome is more commonly associated with systemic manifestations than typical disease, and may be refractory to immunosuppressive treatment. We discuss the application of laboratory (e.g antibodies targeting inner ear antigens) and radiological (PET-CT) aids to disease confirmation and detection of sub-clinical vascular inflammation. As illustrated by the included case description, some patients remain refractory to intense immunosuppression and delineation of adverse prognostic factors which may direct treatment, perhaps including the use of PET-CT, will contribute in the future to improving patient outcomes.

[Auto-immune sensorineural deafness: physiopathology and therapeutic approach]

Sensorineural hearing loss may be due to an autoimmune mechanism. The mechanisms that could induce autoimmune inner ear damage are now better understood, but are not exclusive. Moreover, there is no specific immunologic test available for the diagnosis of autoimmune sensorineural hearing loss, which could also complicate the disease course of other autoimmune systemic diseases. Thus, the incidence of sensorineural autoimmune hearing loss is probably underestimated. The aim of this study was to review the experimental immunologic data in favour of an autoimmune mechanism in this subgroup of sensorineural hearing loss: humoral specific response against inner ear (autoantibodies against a transmembrane transporter) and also cellular response (against cochlin: one of the major proteins expressed in the inner ear). The aim of this review was also to focus on clinical and epidemiological human data that provide evidence for an autoimmune etiopathogeny of some sensorineural hearing loss. Therapeutic options such as immunosuppressive treatments (oral corticosteroids and other immunosuppressive drugs, such as methotrexate and anti-TNFalpha) are also discussed.

Sensorineural hearing loss in systemic lupus erythematosus: case report and literature review

OBJECTIVES

We present a case of systemic lupus erythematosus with symptomatic sensorineural hearing loss which was successfully treated with azathioprine, as assessed both clinically and radiologically. We also present a review of the relevant literature.

CASE REPORT

A woman with systemic lupus erythematosus presented with sensorineural hearing loss, initially on the right and subsequently developing on the left over several months. An audiogram revealed profound neurosensory hearing loss bilaterally. The patient was treated with prednisone 60 mg daily and azathioprine 200 mg daily. An improvement on the left was noted on follow-up audiography as well as on magnetic resonance imaging of the internal auditory canals and surrounding structures.

CONCLUSION

Sensorineural hearing loss has been described in autoimmune disorders but is rare. Aural symptoms have been described, with varying incidences (0-57.5 per cent), in systemic lupus erythematosus. However, symptomatic sensorineural hearing loss is rare in systemic lupus erythematosus. Prednisone appears essential when an immunological or vasculitic cause is found. The use of azathioprine should be considered, as well as follow-up with magnetic resonance imaging to detect improvement.

Diagnostic tests for immunomediated hearing loss: a systematic review

OBJECTIVE

To quantitatively evaluate the diagnostic accuracy of diagnostic tests for immunomediated hearing loss.

DATA SOURCES

We searched Medline and the Cochrane Database of Systematic Reviews for potentially relevant studies.

STUDY SELECTION

Twenty-five studies met the inclusion criteria of this systematic review. The diagnosis of immunomediated hearing loss was based on the clinical presentation and the response to corticosteroid administration.

DATA EXTRACTION

The following data were extracted from the selected studies and entered into a standardised database: population demographics; exclusion and inclusion criteria; diagnostic tests; sensitivity; specificity; the number of true positive, true negative, false positive and false negative values; therapy used, including dose and duration; and delay between symptom onset and therapy commencement.

DATA SYNTHESIS

This systematic review combined data from 679 patients with immunomediated hearing loss, reported by 22 research teams. Substantial heterogeneity was found among the included studies; for this reason, summary sensitivity and specificity values were not computed.

CONCLUSIONS

The results of diagnostic tests for immunomediated hearing loss depend on many factors, and there is a risk of potential bias. This is the first time that such a systematic review has been presented; such a review is a more rigorous method of demonstrating the utility of the available diagnostic tests.

Antibody reactivity to heat shock protein 70 and inner ear-specific proteins in patients with idiopathic sensorineural hearing loss

Deafness is attributable to autoimmunity in a subset of adult patients with sensorineural hearing loss (SNHL) of unknown aetiology. To determine the roles of self-antigens in the pathogenesis of idiopathic SNHL, we analysed antibody responses to the inner ear-specific proteins, cochlin and beta-tectorin as well as the non-specific heat shock protein 70 (HSP70). Recombinant cochlin and beta-tectorin proteins were used in a qualitative Western blot assay for the detection of antigen-specific IgG antibodies in 58 patients with idiopathic SNHL and 28 healthy blood donors. In the same study cohort, we also used a Western blot assay to assess IgG antibody responses to the recombinant human HSP70. Of the 58 patient samples analysed, 19 tested positive to the HSP70, eight to cochlin and one to beta-tectorin, giving a prevalence of 33, 14 and 2%, respectively. Only one patient sample was reactive for HSP70, cochlin and beta-tectorin, seven of the remaining eight cochlin IgG antibody-positive samples were monospecific. Thus, cochlin-specific antibodies were observed predominantly in HSP70 IgG-negative patients demonstrating an additive value for testing this antibody response in patients with idiopathic SNHL.

The effects of the glucocorticoid receptor antagonist RU486 and phospholipase A2 inhibitor quinacrine on acoustic injury of the mouse cochlea

Glucocorticoids are used clinically for the treatment of acoustic injury. However, the protective mechanism of glucocorticoid in acoustic injury has not been completely clarified. Also, the effects of phospholipase A2 (PLA2) on acoustic injury have not been examined to the best of our knowledge. The purpose of the present study was to examine the effects of methylprednisolone, a glucocorticoid receptor inhibitor (RU486) and a phospholipase A2 inhibitor (quinacrine) on cochlear injury induced by acoustic overexposure. Seventy-eight mice were exposed to a 4kHz pure tone at 128dB SPL for 4h. The auditory brainstem response (ABR) was used to examine the hearing thresholds. Cochlear morphology was examined to estimate the outer hair cell loss induced by acoustic overexposure. Methylprednisolone and quinacrine significantly alleviated the hearing threshold shift and hair cell loss induced by acoustic overexposure. RU486 antagonized the protective effect of methylprednisolone. The present findings suggest firstly that glucocorticoids exert protective effects against acoustic injury; secondly, that the protective effect of methylprednisolone was exerted by binding glucocorticoid receptors, and finally that activation of PLA2 may be involved in acoustic injury.

Asymptomatic Sensorineural Hearing Loss in Patients With Systemic Lupus Erythematosus

OBJECTIVE

Hearing loss can accompany systemic lupus erythematosus (SLE). The purpose of this study was to evaluate the prevalence of asymptomatic sensorineural hearing loss (ASNHL) in patients with SLE.

METHODS

Thirty-one unselected consecutive female patients with SLE (American College of Rheumatology criteria, 1982) were evaluated (in a prospective and descriptive study) for evidence of hearing abnormalities. Twenty-five healthy age-matched women served as controls. All patients and control groups underwent both a normal tympanoscopy and an audiometric testing as a prerequisite to be included in the study.

RESULTS

Patients with SLE had a mean age of 35 years (range, 19-64 years) and the follow-up time (median) was 48 months (range, 4-180 months). One of 31 patients was excluded because of middle ear infectious disease. Of the remaining 30 patients, 21 (70%) had impaired hearing; 20 (66%) had sensorineural loss at high frequencies in a bilateral and symmetric way, and one had conductive alteration. Ten patients had normal audiometric studies. Four women in the control group had alterations of the audiometric tests: 3 patients had conductive alteration and the other one had bilateral ASNHL. No statistically significant correlation was found among the presence of ASNHL, the detection of antiphospholipid antibodies, and the treatment with hydroxychloroquine. Also, no correlation was observed between impaired hearing and SLE activity.

CONCLUSION

If it can be established how often this ASNHL progresses to a clinical problem, it can be important that, as part of initial studies, patients with SLE undergo audiometric tests.

Immune-mediated inner-ear disorders in neuro-otology

PURPOSE OF REVIEW

Immune-mediated inner-ear disorders may present to different medical disciplines and new research findings emerge rapidly. The purpose of this review is to draw the different strands together to produce an overview describing the clinical presentation of immune-mediated inner-ear disorders and to discuss useful diagnostic criteria with a focus on tissue-specific and tissue-non-specific antibodies.

RECENT FINDINGS

The importance of diagnosing an immune-mediated inner-ear disorder is highlighted in the context of it being one of few forms of treatable inner-ear disorder with a good response to immunosuppressive therapy. Due to a lack of reliable tests, the criteria upon which the diagnosis of immune-mediated inner-ear disease is based are often arbitrary. Previous and current research focuses mainly on the investigation of the aetiology of immune-mediated disorders, studying the presence of autoantibodies and the antigens responsible for their production. The prognostic and therapeutic values of inner-ear-specific antibodies are still unclear. Various antigens have been suggested. However, most antigens identified have been ubiquitous proteins not specific to the inner ear and therefore lack logical association with localized inner-ear pathology.

SUMMARY

Early diagnosis of immune-mediated inner-ear disorders with prompt treatment may prevent irreversible damage to inner-ear structures. Accordingly, it is important to include immune-mediated inner-ear disorders in the differential diagnosis of patients presenting with 'idiopathic' audiovestibular dysfunction. To enable early diagnosis, we recommend that the current available routine immunological laboratory tests (antinuclear, antineutrophil cytoplasmic, antiendothelial cell, antiphospholipid/anticardiolipin and antithyroid antibodies) are used when assessing a patient with suspected immune-mediated inner-ear disorder.