AAO: Autoimmune and Autoinflammatory (Disease) in Otology: What is New in Immune-Mediated Hearing Loss

Infliximab in Autoimmune Inner Ear Disease: A Case Report

Autoimmune inner ear disease (AIED) is characterized by bilateral, asymmetric, and fluctuating sensorineural hearing loss (SNHL) with no identifiable cause that responds to immunosuppressive therapy. Diagnosis can be challenging due to a lack of standardized diagnostic criteria and pathognomonic tests. The mainstay of treatment is corticosteroids; however, only a small number of patients remain responsive after prolonged use. There are no agreed treatment protocols for AIED following corticosteroids, as there is limited data from randomized controlled trials. We report a case of a 27-year-old man with secondary AIED on a background of ulcerative colitis (UC) who experienced frequent relapses and deterioration in his hearing despite multiple courses of high-dose corticosteroids. He received methotrexate and azathioprine but did not show clinical or audiometric improvement. After the commencement of infliximab infusions, his symptoms of AIED and UC improved, and his hearing remained stable without further use of oral corticosteroid therapy. The available studies on the efficacy of biologic therapy are limited and have produced variable results, with the majority of the data relying mainly on case reports and case series. Large, multicenter randomized controlled trials are required to confirm its efficacy in the management of AIED.

[Cochlear implantation in patients with autoimmune hearing loss]

BACKGROUND

Autoimmune inner ear disease (AIED) manifests with recurrent fluctuating sensorineural hearing loss and vestibular symptoms. Treatment includes steroids and a variety of immunosuppressants. Despite adequate treatment, sensorineural hearing loss can be progressive to the point of deafness. In these patients, a cochlear implant (CI) is indicated. We present the case of a 25-year-old male who underwent cochlear implantation in the left ear. After implantation we noticed brisk variations in impedances which were related to application of the previously prescribed tumor necrosis alpha (TNFα) inhibitor adalimumab.

OBJECTIVE

Can immunomodulatory therapy in AIED patients after CI fitting affect the quality of hearing rehabilitation?

MATERIALS AND METHODS

We documented impedances and speech intelligibility (Freiburg monosyllable test) of our patient for 1 year in dependence on adalimumab therapy.

RESULTS

Directly after implantation, impedances were within the normal range. During the further course, impedances started to rise, and recurrent adjustments of the implant were needed. Adalimumab therapy was reinitiated, which resulted in a subsequent reduction of impedances.

CONCLUSION

Cochlear implantation can be necessary in some AIED patients and poses a sufficient method for hearing rehabilitation. Depending on the activity of the underlying disease, a rise in impedances may occur. Immunomodulatory treatment may therefore be necessary to maintain adequate hearing results with the CI.

A Selection Protocol to Identify Therapeutics to Target NLRP3-Associated Sensory Hearing Loss

OBJECTIVE

We propose a selection process to identify a small molecule inhibitor to treat NLRP3-associated sensory hearing loss.

BACKGROUND

The NLRP3 inflammasome is an innate immune sensor and present in monocytes and macrophages. Once the inflammasome is activated, a cleavage cascade is initiated leading to the release of proinflammatory cytokines IL-1β and IL-18. The NLRP3 inflammasome has been implicated in many causes of hearing loss, including autoimmune disease, tumors, and chronic suppurative otitis media. Although the target has been identified, there is a lack of available therapeutics to treat NLRP3-associated hearing loss.

METHODS

We created a target product profile with specific characteristics that are required for a compound to treat sensory hearing loss. We then looked at available small molecule NLRP3 inhibitors at different stages of development and selected compounds that fit that profile best. Those compounds were then tested for cell toxicity in MTT assays to determine the dosage to be used for efficacy testing. We tested efficacy of a known NLRP3 inhibitor, MCC950, in a proof-of-concept screen on reporter monocytes.

RESULTS

Six compounds were selected that fulfilled our selection criteria for further testing. We found the maximum tolerated dose for each of those compounds that will be used for further efficacy testing. The proof-of-concept efficacy screen on reporter monocytes confirmed that those cells can be used for further efficacy testing.

CONCLUSION

Our selection process and preliminary results provide a promising concept to develop small molecule NLRP3 inhibitors to treat sensory hearing loss.

Global trend analysis, mechanistic insights and future directions of autoimmune ear diseases: Based on comprehensive findings over the past 20 years

BACKGROUND

In recent years, Autoimmune diseases (ADs) and hearing loss are both significant public health burdens worldwide. An increasing number of studies are focusing on the potential link between these two diseases and exploring how hearing loss can be prevented and treated in the context of autoimmune diseases. In response to this focus, it is very necessary to conduct bibliometric analysis and molecular mechanism exploration to provide guidance for the exploration of basic mechanisms and clinical management.

METHOD

Studies focusing on hearing loss and autoimmune disease were extracted from the Web of Science Core Collection database from 2000 to 2024. Bibliometric and visual analysis of the collected publications was conducted using VOSviewer and CiteSpace. The investigation of molecular pathways associated with diseases was carried out in the GeneCards and STRING databases.

RESULTS

A total of 696 papers met the inclusion and exclusion criteria and were chosen for further research. The number of papers on hearing loss and autoimmune diseases is increasing every year. These papers were mainly from 65 countries, led by the United States, China and Italy. These investigations included 3505 authors in total, with Greco A contributing the most publications. Harvard Medical School and Sapienza University Rome were the two institutions with the highest number of publications. Otology & Neurotology was the journal with the highest number of publications. The most common keywords include " sensorineural hearing loss", "endolymphatic hydrops", "management" and "autoimmune", which represent current and prospective future research trends and target topics in the field. Among them, the highest proportion of hearing loss in autoimmune ear diseases is sensorineural hearing loss, and the highest proportion of primary autoimmune ear diseases is Autoimmune inner ear disease. In addition, A total of 295 potential targets common to both diseases were also identified. Their pathogenesis involves cancer pathways, infectious disease pathways, cell senescence, epithelial and myocyte proliferation, hypoxia response, and inflammatory response.

CONCLUSION

This bibliometric analysis reveals global research trends on hearing loss in the context of autoimmune diseases. Based on this, combined with preliminary bioinformatics analysis, a potential yet close link between the autoimmune diseases and hearing loss has been demonstrated. The current study highlights the need to fully consider the common genetic and pathophysiological mechanisms of these two types of diseases to promote interdisciplinary research and the development of personalized treatments for this clinical focus, with particular attention to the elderly population with comorbidity diseases. A deeper understanding of disease mechanisms has also led to advances in the clinical management of autoimmune ear diseases, including diagnosis and treatment.

Mammalian Inner Ear-Resident Immune Cells-A Scoping Review

BACKGROUND

Several studies have demonstrated the presence of resident immune cells in the healthy inner ear.

AIM

This scoping review aimed to systematize this knowledge by collecting the data on resident immune cells in the inner ear of different species under steady-state conditions.

METHODS

The databases PubMed, MEDLINE (Ovid), CINAHL (EBSCO), and LIVIVO were used to identify articles. Systematic reviews, experimental studies, and clinical data in English and German were included without time limitations.

RESULTS

The search yielded 49 eligible articles published between 1979 and 2022. Resident immune cells, including macrophages, lymphocytes, leukocytes, and mast cells, have been observed in various mammalian inner ear structures under steady-state conditions. However, the physiological function of these cells in the healthy cochlea remains unclear, providing an opportunity for basic research in inner ear biology.

CONCLUSIONS

This review highlights the need for further investigation into the role of these cells, which is crucial for advancing the development of therapeutic methods for treating inner ear disorders, potentially transforming the field of otolaryngology and immunology.

Polymer-Based Nanoparticles for Inner Ear Targeted Trans Differentiation Gene Therapy

Hearing loss is a significant disability that often goes under recognised, largely due to poor identification, prevention, and treatment. Steps are being made to amend these pitfalls in the investigation of hearing loss, however, the development of a cure to reverse advanced forms remains distant. This review details some current advances in the treatment of hearing loss, with a particular focus on genetic-based nanotechnology and how it may provide a useful avenue for further research. This review presents a broad background on the pathophysiology of hearing loss and some current interventions. We also highlight some potential genes that may be useful in the amelioration of hearing loss. Pathways of cellular differentiation from stem or supporting cell to functional hair cell are covered in detail, as this mechanism represents a key means of regenerating these cell types. Overall, we believe that polymer-based nanotechnology coupled with novel excipients represents a useful area of further research in the treatment of hearing loss, although further studies in this area are required.

A novel cell-free therapy using exosomes in the inner ear regeneration

Cellular and molecular alterations associated with hearing loss are now better understood with advances in molecular biology. These changes indicate the participation of distinct damage and stress pathways that are unlikely to be fully addressed by conventional pharmaceutical treatment. Sensorineural hearing loss is a common and debilitating condition for which comprehensive pharmacologic intervention is not available. The complex and diverse molecular pathology that underlies hearing loss currently limits our ability to intervene with small molecules. The present review focuses on the potential for the use of extracellular vesicles in otology. It examines a variety of inner ear diseases and hearing loss that may be treatable using exosomes (EXOs). The role of EXOs as carriers for the treatment of diseases related to the inner ear as well as EXOs as biomarkers for the recognition of diseases related to the ear is discussed.

Updates on Genetic Hearing Loss: From Diagnosis to Targeted Therapies

Sensorineural hearing loss (SNHL) is the most common sensory disorder, with a high Mendelian genetic contribution. Considering the genotypic and phenotypic heterogeneity of SNHL, the advent of next-generation sequencing technologies has revolutionized knowledge on its genomic architecture. Nonetheless, the conventional application of panel and exome sequencing in real-world practice is being challenged by the emerging need to explore the diagnostic capability of whole-genome sequencing, which enables the detection of both noncoding and structural variations. Small molecules and gene therapies represent good examples of how breakthroughs in genetic understanding can be translated into targeted therapies for SNHL. For example, targeted small molecules have been used to ameliorate autoinflammatory hearing loss caused by gain-of-function variants of NLRP3 and inner ear proteinopathy with OSBPL2 variants underlying dysfunctional autophagy. Strikingly, the successful outcomes of the first-in-human trial of OTOF gene therapy highlighted its potential in the treatment of various forms of genetic hearing loss. clustered regularly interspaced short palindromic repeats (CRISPR)-based technologies are currently being developed for site-specific genome editing to treat human genetic disorders. These advancements have led to an era of genotype- and mechanism-based precision medicine in SNHL practice.

A systematic review of the clinical evidence for an association between type I hypersensitivity and inner ear disorders

Inner ear disorders have a variety of causes, and many factors can contribute to the exacerbation of cochlear and vestibular pathology. This systematic review aimed to analyze clinical data on the coexistence and potential causal interaction between allergic diseases and inner ear conditions. A search of PubMed and Web of Science identified 724 articles, of which 21 were selected for full-text analysis based on inclusion and exclusion criteria. The epidemiologic evidence found overwhelmingly supports an association between allergic disease and particular inner ear disorders represented by a high prevalence of allergic reactions in some patients with Ménière's disease (MD), idiopathic sudden sensorineural hearing loss (ISSHL), and acute low-tone hearing loss (ALHL). In addition, patients with MD, ISSHL, and ALHL had higher levels of total serum IgE than healthy subjects. Finally, in some cases, changes in cochlear potential may have been induced by antigen exposure, while desensitization alleviated allergy and inner ear-related symptoms. The exact mechanism of interaction between the auditory/vestibular and immune systems is not fully understood, and further clinical and basic research is needed to understand the relationship between the two systems fully.

The Importance of Lassa Fever and Its Disease Management in West Africa

Lassa virus (LASV) is a zoonotic pathogen endemic throughout western Africa and is responsible for a human disease known as Lassa fever (LF). Historically, LASV has been emphasized as one of the greatest public health threats in West Africa, with up to 300,000 cases and 5000 associated deaths per year. This, and the fact that the disease has been reported in travelers, has driven a rapid production of various vaccine candidates. Several of these vaccines are currently in clinical development, despite limitations in understanding the immune response to infection. Alarmingly, the host immune response has been implicated in the induction of sensorineural hearing loss in LF survivors, legitimately raising safety questions about any future vaccines as well as efficacy in preventing potential hearing loss. The objective of this article is to revisit the importance and prevalence of LF in West Africa, with focus on Nigeria, and discuss current therapeutic approaches and ongoing vaccine development. In addition, we aim to emphasize the need for more scientific studies relating to LF-associated hearing loss, and to promote critical discussion about potential risks and benefits of vaccinating the population in endemic regions of West Africa.

Clinical Biomarkers in Otolaryngology-Head and Neck Surgery: Autoimmune Diseases

OBJECTIVE

The purpose of this article is to review the literature and compile promising and clinically relevant biomarkers in autoimmune disease related to otolaryngology-head and neck surgery.

STUDY DESIGN

Narrative review.

METHODS

Pubmed and Google Scholar were queried using combined key words such as "biomarkers" and "otolaryngology." Additional queries were made with combined key words such as "biomarkers" and a particular subspecialty such as "autoimmune" or "Meniere's" to maximize yield of relevant titles. Subsequently, specific biomarkers identified, such as "anti-TPO-antibodies," were used as key words. Relevant titles were reviewed and selected for abstract review. Applicable abstracts were then selected for review of the full text.

RESULTS

Biomarkers that are currently in clinical use for the management of autoimmune diseases within the field of otolaryngology were included in this review. The compiled biomarkers were then detailed individually regarding their molecular characteristics, function, and clinical significance.

CONCLUSIONS

Based on this literature review, there are several biomarkers currently in clinical use within the field of otolaryngology relating to autoimmune diseases. The majority of these biomarkers are in the form of proteins such as Cogan peptide and c-ANCA. This survey may serve as a comprehensive resource on biomarkers for autoimmune diseases in clinical otolaryngology.

The First 100 Children Treated in a Newly Established Pediatric Vertigo Center

BACKGROUND

Correctly diagnosing dizziness in children is essential for appropriate management; nevertheless, healthcare professionals face challenges due to children's limited ability to describe their symptoms and their cooperation during physical examination. The objective of this study is to describe the first 100 patients seen at a newly established pediatric vertigo center.

METHODS

This is a retrospective review of a consecutive series of 100 patients seen at our pediatric vertigo clinic in a tertiary referral center from August 2019 until June 2022. Comprehensive clinical data were collected. The diagnoses were established by 2 pediatric otolaryngologists based on validated diagnostic criteria. Trends in diagnosis, investigation, and treatment of these patients were analyzed.

RESULTS

A total of 100 children were included in the study. Vestibular migraine was the most common diagnosis (20%) followed by benign paroxysmal vertigo of childhood (14%). Eleven patients had combined pathologies. Fifteen out of 70 children (21%) had abnormal audiograms, 30 out of 48 children (62.5%) had abnormal vestibular testing, and 6 out of 31 (19%) patients had abnormal imaging. Fifty-one children received medical treatment, 23 received vestibular physiotherapy, and 9 patients had particle repositioning maneuvers; moreover, 17 of these patients received multimodal treatment.

CONCLUSIONS

Our analysis suggests that imaging and audiology testing have relatively low yield in the assessment of pediatric vertigo. On the other hand, vestibular testing detected a high proportion of abnormalities, such as saccadic pursuit, vertical nystagmus, central positional nystagmus, and abnormal directional preponderance, particularly associated with vestibular migraine. Given the complexity of diagnosing vertigo in children, it is critical to establish multidisciplinary specialized centers capable of providing accurate diagnosis and treatment for these children.

Underestimated Subsequent Sensorineural Hearing Loss after Septicemia

Background and Objectives: Hearing loss after septicemia has been found in mice; the long-term risk increased 50-fold in young adults in a previous study. Hearing loss after septicemia has not received much attention. The aim of this study was to assess the relationship between septicemia and subsequent hearing loss. Materials and Methods: Inpatient data were obtained from the Taiwan Insurance Database. We defined patients with sensorineural hearing loss and excluded patients under 18 years of age. Patients without hearing loss were selected as controls at a frequency of 1:5. The date of admission was defined as the date of diagnosis. Comorbidities in the 3 years preceding the date of diagnosis were retrieved retrospectively. Associations with hearing loss were established by multiple logistic regression and forward stepwise selection. Results: The odds ratio (OR) for the association between sepsis and hearing loss was 3.052 (95% CI: 1.583-5.884). Autoimmune disease (OR: 5.828 (95% CI: 1.906-17.816)), brain injury (OR: 2.264 (95% CI: 1.212-4.229)) and ischemic stroke (OR: 1.47 (95% CI: 1.087-1.988)) were associated with hearing loss. Conclusions: Our study shows that hearing loss occurred after septicemia. Apoptosis caused by sepsis and ischemia can lead to hair cell damage, leading to hearing loss. Clinicians should be aware of possible subsequent complications of septicemia and provide appropriate treatment and prevention strategies for complications.

Secondary autoimmune immune ear disease (AIED): a systematic review and meta-analysis on vestibular manifestations of systemic autoimmune and inflammatory disorders

Secondary autoimmune inner ear disease (AIED) is often bilateral and asymmetric in patients presenting with audiovestibular symptoms due to a systemic autoimmune disease. This systematic review and meta-analysis are aimed at identifying and highlighting patterns in prevalence of vestibular dysfunction, symptom presentation, and diagnostic methods in extant literature by combining clinical context from case reports with quantitative analyses from cohort studies. Screening of articles by title, abstract, and full text was completed by four reviewers (K.Z., A.L., S.C., and S.J.). In this study, we grouped secondary AIED and systemic autoimmune diseases by pathophysiologic mechanism: (1) connective tissue disease (CTD), (2) vasculitides (VAS), (3) systemic inflammatory disorders (SID), and (4) other immune-mediated disorders (OIMD). The search for AIED disease identified 120 articles (cohorts and case reports) that met the final inclusion criteria. All 120 were included in the qualitative review, and 54 articles were included for meta-analysis. Of these 54 articles, 22 included a control group (CwC). Ninety individual cases or patient presentations from 66 articles were included for analysis in addition to the 54 cohort articles. Secondary AIED does not have a diagnostic algorithm for managing vestibular symptoms. The management of audiovestibular symptoms requires close collaboration between otolaryngologists and rheumatologists to preserve end-organ function of the ear. To improve our ability to understand the impact on the vestibular system, vestibular clinicians need to develop a standardized reporting method. Clinical presentation should frequently be paired with vestibular testing to contextually investigate symptom severity and provide higher quality care.

Dexamethasone treatment of murine auditory hair cells and cochlear explants attenuates tumor necrosis factor-α-initiated apoptotic damage

The most common cause of sensorineural hearing loss is damage of auditory hair cells. Tumor necrosis factor-alpha (TNF-α) is closely associated with sensorineural hearing loss. The present study examined the preconditioning effect of dexamethasone (DEX) on TNF-α-induced ototoxicity in mouse auditory hair cells (HEI-OC1) and cochlear explants. Treatment of HEI-OC1 with 10 ng/ml TNF-α for 24 h decreased cell viability, increased the accumulation of reactive oxygen species (ROS), and induced caspase-mediated apoptotic signaling pathways. Pretreatment with 10 nM DEX for 6 h before TNF-α exposure restored cell viability, decreased ROS accumulation, and attenuated apoptotic signaling activation induced by TNF-α. Incubation of cochlear explants with 20 ng/ml TNF-α for 24 h resulted in significant loss of both inner hair cells (IHCs) and outer hair cells (OHCs) and an increase in apoptotic activation accessed by annexin V staining. The cochlear explants pre-incubated with 10 nM DEX attenuated TNF-α ototoxicity in both IHCs and OHCs and apoptotic cell death. These results indicated that DEX plays a protective role in ototoxicity induced by TNF-α through attenuation of caspase-dependent apoptosis signaling pathway and ROS accumulation.

A Continuously Worn Dual Temperature Sensor System for Accurate Monitoring of Core Body Temperature from the Ear Canal

The objective of this work was to develop a temperature sensor system that accurately measures core body temperature from an ear-worn device. Two digital temperature sensors were embedded in a hearing aid shell along the thermal gradient of the ear canal to form a linear heat balance relationship. This relationship was used to determine best fit parameters for estimating body temperature. The predicted body temperatures resulted in intersubject limits of agreement (LOA) of ±0.49 °C over a range of physiologic and ambient temperatures without calibration. The newly developed hearing aid-based temperature sensor system can estimate core body temperature at an accuracy level equal to or better than many devices currently on the market. An accurate, continuously worn, temperature monitoring and tracking device may help provide early detection of illnesses, which could prove especially beneficial during pandemics and in the elderly demographic of hearing aid wearers.

Relapsing autoimmune inner ear disease with significant response to methotrexate and azathioprine combination therapy: A case report and mini literature review

RATIONALE

Autoimmune inner ear disease typically presents with bilateral hearing loss that progresses over weeks or months though its mechanisms are unknown. Corticosteroids are the first-line treatment, but their responses are variable and relapses are frequent. Thus, many experts have sought to replace corticosteroids with immunosuppressive agents.

PATIENT CONCERNS

A 35-year-old woman experienced a progressive hearing impairment, initially on the left side and later becoming bilateral. Her response to corticosteroid monotherapy was temporary, and there have been two relapse episodes over several months.

DIAGNOSES

Autoimmune inner ear disease was considered due to evidence of autoimmunity combined with a clinical course of bilateral and recurrent sensorineural hearing loss and a partial response to corticosteroid therapy.

INTERVENTIONS

The patient received a 3-day mini-pulse of methylprednisolone at 250 mg/d, followed by 12 mg/d maintenance, and concurrently began an azathioprine regimen gradually increasing to 100 mg/day as a corticosteroid-sparing agent.

OUTCOMES

Three weeks after immunosuppressive therapy, hearing and pure-tone audiometry improved, and after 7 weeks, methylprednisolone was tapered to 8 mg/d. The dosage was further reduced by adding methotrexate at 7.5 mg/week, resulting in a reduction to 4 mg/d as maintenance therapy after 4 weeks.

LESSONS

For patients who are unresponsive to corticosteroids or experience difficulty tolerating them, a combination therapy of methotrexate and azathioprine is recommended as a viable alternative as this regimen is well-tolerated and yields positive outcomes.

Whole transcriptome sequencing analysis of blood plasma-derived exosomes from immune-related hearing loss

BACKGROUND

Early diagnosis of immune-related hearing loss and timely treatment can prevent structural damage to the inner ear and contribute to hearing retention. Exosomal miRNAs, lncRNAs and proteins have great prospects as novel biomarkers for clinical diagnosis. Our study aimed to investigate the molecular mechanisms of exosomes or exosomal ceRNA regulatory networks in immune-related hearing loss.

METHODS

An immune-related hearing loss mice model was constructed by injection with inner ear antigen, and then the blood plasma samples of the mice were collected for exosomes isolation by ultra-centrifugation. Subsequently, the different exosomes were sent for whole transcriptome sequencing using Illumina platform. Finally, a ceRNA pair was chosen for validation by RT-qPCR and dual luciferase reporter gene assay.

RESULTS

The exosomes were successfully extracted from the blood samples of the control and the immune-related hearing loss mice. After sequencing, 94 differentially expressed (DE) lncRNAs, 612 DEmRNAs, and 100 DEmiRNAs were found in the immune-related hearing loss-associated exosomes. Afterwards, ceRNA regulatory networks consisting of 74 lncRNAs, 28 miRNAs and 256 mRNAs were proposed, and the genes in the ceRNA regulatory networks were significantly enriched in 34 GO terms of biological processes and 9 KEGG pathways. Finally, Gm9866 and Dusp7 were significantly up-regulated, while miR-185-5p level was declined in the exosomes from immune-related hearing loss, and Gm9866, miR-185-5p and Dusp7 interacted with each other.

CONCLUSIONS

Gm9866-miR-185-5p-Dusp7 was confirmed to be closely correlated with the occurrence and progression of immune-related hearing loss.

Sex differences in autoimmune inner ear disease treatment and audiological outcomes

OBJECTIVE

The primary objective of this study was to assess possible sex-related differences in AIED treatment. The secondary aim was to assess the long-term outcomes of treatment using pre- and post-treatment audiometry and speech discrimination scores.

METHODS

Adult patients with a diagnosis of AIED who were treated for their condition at the senior author's (RTS) practice from 2010 to 2022 were included in this study. Patients were grouped as males or females for further analysis and comparison. Data included past medical history, medication use, surgical history and social history. Air-conduction thresholds (500 to 8000 Hz) were collected and averaged into discrete variables for pre- and post-treatment. The change (∆) and percent change (%∆) of these variables following therapy were analyzed. Speech discrimination score (SDS) testing results were taken at the same time points as pure tone averages, and patients were sub-stratified based on evidence of improvement in SDS and compared accordingly.

RESULTS

One hundred eighty-four patients (78 male/106 female) were included in this study. The mean age of the male participants was 57.18 ± 15.92 years, and the mean age of the female participants was 53.49 ± 16.04 years (p = 0.220). Comorbid autoimmune disease (AD) was more prevalent in females than in males (38.7 % vs. 16.7 %, p = 0.001). Of the patients treated with oral steroids, females received significantly more courses than males (2.554 ± 2.078 vs. 1.946 ± 1.301, p = 0.020). However, the average duration of oral steroids used per trial did not differ significantly between males and females (21.02 ± 18.05 vs. 20.62 ± 7.49, p = 0.135). Audiological results demonstrated that the change (∆) in pure tone average (PTA) at 0.5, 1, 2, and 3 kHz (-4.21 ± 6.394 vs. -3.91 ± 6.105) and high-frequency pure tone average (HFPTA) at 4, 6, and 8 kHz (-4.55 ± 6.544 vs. -2.19 ± 6.842) was not significantly different between the sexes following treatment (p = 0.376 and p = 0.101, respectively). Similarly, the percentage change (%∆) in PTA (-13.17 % vs. -15.01 %) and HFPTA (-8.50 % vs. -6.76 %) also did not differ significantly between males and females (p = 0.900 and p = 0.367, respectively). One hundred-five (57.1 %) patients qualified for the SDS improvement subgroup for analysis, with 50 (47.6 %) being male and 55 (51.9 %) being female (p = 0.159). The change (∆) in SDS (15.12 ± 21.159 vs. 10.62 ± 19.206) and the percentage change (%∆) in SDS (16.71 % vs. 12.40 %) also showed no significant difference between male and female patients (p = 0.312 and p = 0.313, respectively).

CONCLUSION

AIED is not a uniform condition regarding clinical presentation, audiological findings or progression, nor is its treatment straightforward. The utilization and duration of cytotoxic medications, as well as PTA and SDS findings, did not differ between the sexes. However, significantly more courses of oral steroids were prescribed to females than males. Sex as a biological variable and its implications in the pathogenesis and treatment of AIED warrant further study.

[Autoimmune hearing loss and a chance of its development in children: literature review and own observations]

Autoimmune sensorineural hearing loss (AiSNHL) is an uncommon auditory disorder characterized by rapidly progressive bilateral hearing loss and a positive clinical response to treatment with corticosteroids and cytostatics. The prevalence of the disease in the adult population is less than 1% among all cases of subacute and permanent sensorineural hearing loss (precise data are unknown), it is even rarer in children. AiSNHL can be primary (isolated, organ-specific) or secondary (manifestation of another systemic autoimmune disease). The pathogenesis of AiSNHL is based on the proliferation of autoaggressive T cells and the pathological production of autoantibodies to the protein structures of the inner ear, which leads to damage to various parts of the cochlea (possibly also to the retrocochlear parts of the auditory system), less frequently to the vestibular labyrinth. Pathologically, the disease is most often represented by cochlear vasculitis with degeneration of the vascular stria, damage to hair cells and spiral ganglion cells, and endolymphatic hydrops. In 50% of cases, the result of autoimmune inflammation may be fibrosis and/or ossification of the cochlea. The most characteristic symptoms of AiSNHL at any age are episodes of sudden progression of hearing loss, fluctuations of hearing thresholds, and bilateral, often asymmetric impairments. The article presents contemporary ideas of the clinical and audiological manifestations of AiSNHL, the possibilities of diagnosing and treating the disease, and highlights the current approaches to (re)habilitation. Along with literature data, two own clinical cases of an extremely rare pediatric AiSNHL are given.

Repurposable Drugs That Interact with Steroid Responsive Gene Targets for Inner Ear Disease

Corticosteroids, oral or transtympanic, remain the mainstay for inner ear diseases characterized by hearing fluctuation or sudden changes in hearing, including sudden sensorineural hearing loss (SSNHL), Meniere's disease (MD), and autoimmune inner ear disease (AIED). Despite their use across these diseases, the rate of complete recovery remains low, and results across the literature demonstrates significant heterogeneity with respect to the effect of corticosteroids, suggesting a need to identify more efficacious treatment options. Previously, our group has cross-referenced steroid-responsive genes in the cochlea with published single-cell and single-nucleus transcriptome datasets to demonstrate that steroid-responsive differentially regulated genes are expressed in spiral ganglion neurons (SGN) and stria vascularis (SV) cell types. These differentially regulated genes represent potential druggable gene targets. We utilized multiple gene target databases (DrugBank, Pharos, and LINCS) to identify orally administered, FDA approved medications that potentially target these genes. We identified 42 candidate drugs that have been shown to interact with these genes, with an emphasis on safety profile, and tolerability. This study utilizes multiple databases to identify drugs that can target a number of druggable genes in otologic disorders that are commonly treated with steroids, providing a basis for establishing novel repurposing treatment trials.

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.

Role of Inner Ear Macrophages and Autoimmune/Autoinflammatory Mechanisms in the Pathophysiology of Inner Ear Disease

Macrophages play important roles in tissue homeostasis and inflammation. Recent studies have revealed that macrophages are dispersed in the inner ear and may play essential roles in eliciting an immune response. Autoinflammatory diseases comprise a family of immune-mediated diseases, some of which involve sensorineural hearing loss, indicating that similar mechanisms may underlie the pathogenesis of immune-mediated hearing loss. Autoimmune inner ear disease (AIED) is an idiopathic disorder characterized by unexpected hearing loss. Tissue macrophages in the inner ear represent a potential target for modulation of the local immune response in patients with AIED/autoinflammatory diseases. In this review, we describe the relationship between cochlear macrophages and the pathophysiology of AIED/autoinflammatory disease.

Combination Immunosuppressive Therapy in Primary Autoimmune Inner Ear Disease in Pregnancy

Objective. Autoimmune inner ear disease (AIED) is a rare disorder characterized by rapidly progressive, sensorineural hearing loss that demonstrates good responsiveness to corticosteroid and immunosuppressive therapy. The pathophysiology is likely driven by chronic trafficking of immune cells into the inner ear, targeting inner ear proteins to coordinate inflammation. Suppression or modulation of the immune response can minimize cochleitis allowing for potential recovery of hearing. It is an otologic emergency requiring a multidisciplinary approach to management to commence immunosuppressive therapy. This can be achieved using steroids, immunomodulators, plasmapheresis, intravenous immunoglobulin, or biologic agents. Treatment decisions are further complicated in pregnancy and require supervision by an obstetrician and maternal-fetal medicine (MFM) specialist. Concerns include safe dosing of steroids and potential for transplacental migration of immune complexes. We provide the first comprehensive literature review on AIED and its implications in pregnancy. We frame our discussion in the context of the second reported case of primary AIED in pregnancy and the first to show excellent response to immunosuppressive therapy. Methods. We reviewed the presented case and literature on AIED. Results. A 27-year-old, pregnant, HSP-70 positive woman was diagnosed with AIED and had excellent recovery of hearing and balance following a combination of steroid treatment, augmented by oral immunomodulators, plasmapheresis, and IVIG. Conclusion. AIED is a diagnostic challenge, and treatment considerations are complex when encountered in pregnancy. Management requires multidisciplinary involvement between otolaryngologists, immunologists, and obstetricians to balance maternal and fetal health outcomes.

Up-Regulated Expression of Interferon-Gamma, Interleukin-6 and Tumor Necrosis Factor-Alpha in the Endolymphatic Sac of Meniere's Disease Suggesting the Local Inflammatory Response Underlies the Mechanism of This Disease

Background

Immune mediated inflammatory changes affecting the endolymphatic sac (ES) may underlie the pathology of Meniere's disease (MD). The aim of the present study was to explore the differentially expressed cytokines in ES luminal fluid (ELF) of patients with MD, and the correlation between the expression of cytokines in the ELF with that in the serum was determined by quantitatively analyzing the cytokines in human ELF and serum.

Methods

Human ELF, serum and ES tissues were collected from patients with unilateral MD and patients with acoustic neuroma (AN) during surgery. The Simoa Cytokine 6-Plex Panel kit was used to analyze the levels of cytokines in the ELF and blood samples of the patients. Immunohistochemistry and immunofluorescence were subsequently used to validate the relative expression levels of the cytokines in MD.

Results

Significant differences were identified in the expression levels of interferon-γ (IFN-γ) (P < 0.001), interleukin (IL)-6 (P = 0.008) and tumor necrosis factor-α (TNF-α) (P = 0.036) in the luminal fluid of the ES comparing between the MD and AN groups. By contrast, the levels of IFN-γ, IL-10, IL-12p70, IL-17A, IL-6 and TNF-α in the serum of the MD group were not significantly different from those of either the AN group or healthy control subjects. In addition, no significant correlations in the expression levels of cytokines compared between the ELF and serum were found for the patients in either the MD or the AN group. Finally, the detection of positive expression of TNF-α, IL-6 and IFN-γ in the epithelial cells of the majority of ES specimens from patients with MD confirmed the up-regulated expression of these cytokines in the ES of patients with MD.

Conclusions

The identification of up-regulated expression levels of TNF-α, IL-6 and IFN-γ in the ELF in the present study has provided direct evidence for an increased immunologic activity in the microenvironment of the ES in patients with unilateral MD, may suggest the local inflammatory response underlies the mechanism of this disease.

The global hearing therapeutic pipeline: 2021

Hearing loss is a serious condition affecting more than 1.5 billion people globally. Many affected people benefit from the use of devices, such as hearing aids, but these do not restore natural hearing, and many users still struggle to follow speech in the presence of background noise. Consequently, there is rapid growth in work to discover therapeutics to address this need. Our analysis of the therapeutic pipeline for inner ear and central processing disorders identified 23 assets in clinical trials and 56 in preclinical development, of which 25% have entered the pipeline in the past three years. The innovative potential of this pipeline is encouraging, but there are translational hurdles to be overcome. We highlight challenges for the pipeline and comment on opportunities to support and strengthen it.

Hearing restoration and the stria vascularis: evidence for the role of the immune system in hearing restoration

PURPOSE OF REVIEW

This article reviews the current literature regarding the pathogenesis of immune-mediated sensorineural hearing loss, utilizes previously published single-nucleus transcriptional profiles to characterize cytokine and cytokine receptor expression in the adult stria vascularis cell types to support immune system interaction with the stria vascularis and reviews the current literature on immunomodulatory agents currently being used for hearing-restoration treatment.

RECENT FINDINGS

The literature review highlights recent studies that elucidate many cytokines and immune markers, which have been linked to various immune-mediated disease processes that have been observed with sensorineural hearing loss within the stria vascularis and highlights recent publications studying therapeutic targets for these pathways.

SUMMARY

This review highlights the current literature regarding the pathogenesis of immune-mediated hearing loss. The role of cochlear structures in human temporal bones from patients with immune-mediated sensorineural hearing loss are highlighted, and we review cytokine signalling pathways relevant to immune-mediated sensorineural hearing loss and localize genes encoding both cytokine and cytokine receptors involved in these pathways. Finally, we review immunomodulatory therapeutics in light of these findings and point to opportunities for the application of novel therapeutics by targeting these signalling pathways.

The Correlation of Clinical Corticosteroid Responsiveness With Expression of IL-6 in Peripheral Blood Immune Cells (PBMC) in Patients With Autoimmune Inner Ear Disease (AIED)

HYPOTHESIS

Autoimmune inner ear disease (AIED) patients will differentially express interleukin (IL)-6 based on corticosteroid responsiveness.

BACKGROUND

AIED is characterized by periods of acute sensorineural hearing loss (SNHL). In a majority of patients corticosteroid responsiveness is lost over time. The mechanisms that control corticosteroid responsiveness have not been fully elucidated.

METHODS

Thirty-five AIED patients and 13 age-matched control subjects were enrolled in this study. Steroid responsive (n = 15) and steroid nonresponsive AIED patients (n = 20) were characterized based on audiometry before and after treatment for acute SNHL. Plasma and peripheral blood mononuclear cells (PBMC) were obtained at the time of acute SNHL to quantify plasma IL-6, soluble IL-6 receptor (sIL-6R), and C-C Motif Chemokine Ligand 3 (CCL3). PBMCs were stimulated with dexamethasone and release of soluble IL-6, sIL-6R, and CCL3 protein into conditioned supernatants was measured. Plasma IL-6 was also correlated to serum c-reactive protein (CRP), cardiac CRP, erythrocyte sedimentation rate.

RESULTS

Statistically significant differences were observed in the plasma IL-6 between AIED patients and controls (2.37 versus 2.03 pg/ml, p < 0.01), plasma IL-6, and CCL3 between responders and nonresponders (0.136 versus 3.84 pg/ml, p < 0.005; 30.5 versus 32.4, p < 0.05) and released IL-6 from dexamethasone stimulated PBMC in AIED patients compared with controls (0.54 versus 1.12 pg/ml, p < 0.001). There was a correlation between plasma IL-6 levels of AIED patients to both serum CRP and cardiac CRP (R2 = 0.83, R2 = 0.88).

CONCLUSIONS

We observed AIED patients, specifically nonresponders expressed greater levels of IL-6. Elevated IL-6 levels in AIED patients correlated with CRP levels, providing a commonly available laboratory test that may aid in rapid clinical decision-making in these patients.

Construction of an MRI-based decision tree to differentiate autoimmune and autoinflammatory inner ear disease from chronic otitis media with sensorineural hearing loss

Autoimmune and autoinflammatory inner ear diseases (AIED/AID) are characterized by the symptom of sensorineural hearing loss (SNHL). To date, standardized diagnostic tools for AIED/AID are lacking, and clinically differentiating AIED/AID from chronic otitis media (COM) with SNHL is challenging. This retrospective study aimed to construct a magnetic resonance imaging (MRI)-based decision tree using classification and regression tree (CART) analysis to distinguish AIED/AID from COM. In total, 67 patients were enrolled between January 2004 and October 2019, comprising AIED/AID (n = 18), COM (n = 24), and control groups (n = 25). All patients underwent 3 T temporal bone MRI, including post-contrast T1-weighted images (postT1WI) and post-contrast FLAIR images (postFLAIR). Two radiologists evaluated the presence of otomastoid effusion and inner ear contrast-enhancement on MRI. A CART decision tree model was constructed using MRI features to differentiate AIED/AID from COM and control groups, and diagnostic performance was analyzed. High-intensity bilateral effusion (61.1%) and inner ear enhancement (postFLAIR, 93.8%; postT1WI, 61.1%) were the most common findings in the AIED/AID group. We constructed two CART decision tree models; the first used effusion amount as the first partitioning node and postT1WI-inner ear enhancement as the second node, whereas the second comprised two partitioning nodes with the degree of postFLAIR-enhancement of the inner ear. The first and second models enabled distinction of AIED/AID from COM with high specificity (100% and 94.3%, respectively). The amount of effusion and the degree of inner ear enhancement on MRI may facilitate the distinction between AIED/AID and COM with SNHL using decision tree models, thereby contributing to early diagnosis and intervention.

Clinical and Cytokine Profile in Patients with Early and Late Onset Meniere Disease

BACKGROUND

Meniere disease (MD) is an inner ear disorder associated with comorbidities such as autoimmune diseases or migraine. This study describes clinical and cytokine profiles in MD according to the age of onset of the condition.

METHODS

A cross-sectional study including 83 MD patients: 44 with early-onset MD (EOMD, <35 years old), and 39 with late-onset MD (LOMD, >50 years old), 64 patients with migraine and 55 controls was carried out. Clinical variables and cytokines levels of CCL3, CCL4, CCL18, CCL22, CXCL,1 and IL-1β were compared among the different groups.

RESULTS

CCL18 levels were higher in patients with migraine or MD than in controls. Elevated levels of IL-1β were observed in 11.4% EOMD and in 10.3% LOMD patients and these levels were not dependent on the age of individuals. EOMD had a longer duration of the disease (p = 0.004) and a higher prevalence of migraine than LOMD (p = 0.045).

CONCLUSIONS

Patients with EOMD have a higher prevalence of migraine than LOMD, but migraine is not associated with any cytokine profile in patients with MD. The levels of CCL18, CCL3, and CXCL4 were different between patients with MD or migraine and controls.

Progressive and Degenerative Peripheral Vestibular Disorders

Initial diagnosis of peripheral vestibulopathy requires a detailed history, physical examination, and, in some cases, audiovestibular testing, radiographic imaging, or serology. Differentiation of a peripheral vestibulopathy as progressive or degenerative is often nuanced and influenced by a characterization of a patient's symptoms or natural history over time. A diverse group of vestibular pathology may fit into this category, including Ménière's disease, autoimmune conditions, congenital pathologies, ototoxic medications, radiation therapy, and perilymphatic fistula. Differentiation among these entities may be guided by initial or subsequent symptomatology, with various combinations of audiovestibular testing, serology, and imaging. Treatment options are disparate and disease-specific, ranging from observation to medical management or surgical intervention, underscoring the need for astute investigation and diagnosis.

Immune-Mediated Sensorineural Hearing Loss in the Pediatric Population

A case series with chart review of pediatric patients with immune-mediated sensorineural hearing loss, including sudden sensorineural hearing loss and autoimmune-mediated hearing loss, was performed. Ninety-eight patients with sensorineural hearing loss were reviewed, and 41 patients met the inclusion criteria, which included corticosteroid therapy for a decline in sensorineural hearing. The primary outcome was the corticosteroid response rate: 61% of patients responded. The secondary outcome was a sustained response following multiple courses of corticosteroids for additional hearing loss, which correlated with timely corticosteroid treatment: 57% showed sustained response with multiple treatments, but as anticipated, patients were more likely to respond when treated promptly. Sustained responses fell over time with multiple treatments. These data demonstrate pediatric immune-mediated sensorineural hearing loss is corticosteroid responsive in at a rate similar to their adult counterparts and should be considered for similar treatment approaches.

Biologics for Immune-Mediated Sensorineural Hearing Loss

Immune-mediated hearing losses include autoimmune inner ear disease, sudden sensorineural hearing loss, and Meniere's disease. Standard therapy for an acute decline in hearing is timely use of corticosteroids. Although 60% to 70% of patients are initially corticosteroid-responsive, that responsiveness is lost over time. In corticosteroid-resistant patients, increased expression of interleukin (IL)-1 is observed, and these patients may benefit from IL-1 inhibition. Autoinflammatory diseases are characterized by dysregulation of the innate immune response, clinically include sensorineural hearing loss, and benefit from IL-1 inhibition, thereby further establishing the relationship of IL-1 with immune-mediated sensorineural hearing loss.

Biologics in Otolaryngology: Past, Present, and Future

Biologics have been widely adopted in multiple subspecialties of otolaryngology. This article provides an overview of past, present, and future uses of biologics in otolaryngology with emphasis on allergic rhinitis, chronic rhinosinusitis with polyposis, head and neck squamous cell carcinoma, salivary and skull base tumors, hearing loss, and other otologic disorders.

Hearing loss in inner ear and systemic autoimmune disease: A systematic review of post-cochlear implantation outcomes

OBJECTIVES

To assess outcomes following cochlear implantation (CI) in patients with hearing loss secondary to primary or secondary autoimmune inner ear disease (AIED).

METHODS

A systematic review and narrative synthesis was completed according to PRISMA guidelines. Databases searched included MEDLINE, PubMed, EMBASE, Web of Science, Cochrane Collection, and ClinicalTrials.gov. No limits were placed on year of publication or language.

RESULTS

A total of 551 studies were identified, of which 29 were included after removal of duplicates, and screening the title, abstract, and full text. All except one study were OCEBM grade IV. 114 of 115 patients displayed improvement in hearing following cochlear implantation. With implant use, roughly a third of these patients had hearing that improved over time, a third improved and plateaued, and a third remained stable. There was no additional risk of perioperative complications found in AIED patients compared what is generally accepted in general cochlear implantation, although two episodes of device failure after 6 months were noted, and four patients with secondary AIED displayed poor initial audiological outcomes.

CONCLUSION

CI in both primary and secondary AIED provides marked improvement in hearing. Early CI may be a valid management option, provide long-lasting hearing in patients and reduce the side effects of long-term systemic immunosuppressants. However, patients should be counseled residual hearing may be lost if there is cochlear ossification or fibrosis which may make implant insertion more traumatic.

LEVEL OF EVIDENCE

NA.

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.

Evaluation of inner ear and hearing functions in lichen planus patients

BACKGROUND

Lichen planus (LP), which affects skin, nails, hair, and mucosal surfaces, is a chronic, autoimmune, and inflammatory disease, and autoimmune diseases may affect the inner ear.

AIMS

This study aims to investigate hearing and inner ear functions of the LP patients.

PATIENTS/METHODS

The present study was formed by 49 patients who were clinically and histopathologically diagnosed with LP and did not receive any treatment. The healthy group consisted of 52 healthy individuals. Pure tone audiometry (PTA) and distortion product otoacoustic emission tests were used in the hearing evaluation.

RESULTS

At frequencies of 1, 2, 4, 6, and 8 kHz in the right ear and 0.5, 1, 2, 4, 6, and 8 kHz in the left ear in PTA, the lichen group's hearing thresholds were higher than the healthy group's. Upon comparing the hearing thresholds of LP patients with oral mucosa involvement and LP patients without oral mucosa involvement, there were significant differences between the groups at 1, 4, and 8 kHz in the right ear and at 0.25, 0.5, 2, 4, 6, and 8 kHz in the left ear.

CONCLUSION

Because of the increasing hearing thresholds, we think that hearing and inner ear functions of LP patients, particularly with oral mucosal involvement, are negatively affected.

Selected Otologic Disorders Causing Dizziness

PURPOSE OF REVIEW

This article details updated clinical presentations and current treatment paradigms of the common otologic disorders that may present to the neurologist for vertigo, including Ménière disease, superior semicircular canal dehiscence syndrome, perilymphatic fistula, barotrauma, cholesteatoma, Ramsay Hunt syndrome, enlarged vestibular aqueduct syndrome, and autoimmune inner ear disease including Cogan syndrome.

RECENT FINDINGS

The recent data on modern imaging techniques with three-dimensional delayed IV contrast in Ménière disease, findings on the clinical and testing parameters to diagnose semicircular canal dehiscence and barotrauma, and clinical findings in Ramsay Hunt syndrome, cholesteatoma, and enlarged vestibular aqueduct syndrome are discussed in the article. The most recent findings on the treatment and evaluation of autoimmune inner ear disease and Cogan syndrome are also covered.

SUMMARY

This article discusses the common clinical otologic entities in patients who may present to the neurologist for vertigo, and it can be used as a guide in the diagnosis of these conditions with the use of auditory, vestibular, and imaging results.

The Pathogenesis of secondary forms of Autoimmune Inner Ear Disease (AIED): advancing beyond the audiogram data

INTRODUCTION

Autoimmune Inner Ear Disease (AIED) can be of a primary or secondary type. To date, a clear pathogenesis of the disease is still not available. Focusing on the secondary forms of AIED, the aim of this review is to (i) assess and describe the hearing involvement in patients affected by autoimmune diseases, (ii) describe the possible association between clinical features (among serological/laboratory data and disease activity/duration) and hearing impairment, (iii) show evidence connecting the AIED types with various etiopathogenetic mechanisms.

AREAS COVERED

A PRISMA-compliant systematic review was performed. Medline, Cochrane, Embase, and Cinahl were searched from 1 January 2015 through to 5 August 2020. Overall, 16 studies (involving 1043 participants) were included in the review. The data in the literature suggested that bilateral mild-to-moderate sensorineural hearing loss is a commonly reported clinical symptom of AIED.

EXPERT OPINION

Patients with systemic autoimmune disorders present a cochlear injury which might be associated with the humoral and/or cellular immune response against the inner ear. To date, AIED pathogenesis remains an open issue, due to the rarity of these clinical entities and due to the difficulties in investigating the inner ear immunology, considering the inner ear inaccessibility for tissue sampling.

Case Report: Anti-NMDA Receptor Encephalitis With Bilateral Hearing Loss as the Initial Symptom

Introduction: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disease associated with the NMDA receptor. This paper describes a patient who presented with bilateral hearing loss as the initial symptom of anti-NMDAR encephalitis.

Case Report: We describe a 31-year-old young female with anti-NMDAR encephalitis who presented with bilateral severe hearing loss after brief loss of consciousness and then accompanied by other symptoms, such as generalized tonic–clonic seizures, manic episodes, excessive salivation, severe cognitive impairment, and complex non-convulsive status epilepticus. Great improvement was achieved by a combined treatment of steroid, IVIG, and plasmapheresis, especially after surgical removal of the ovarian teratoma. When she was discharged on hospital day 43, her hearing loss obtained a significant improvement.

Conclusion: This case study and literature review investigated the impairment of hearing loss and its subsequent treatment in patients with anti-NMDAR encephalitis.

Hearing loss in patients with systemic lupus erythematosus: A systematic review and meta-analysis

OBJECTIVE

To determine the prevalence of hearing loss (HL) in patients with systemic lupus erythematosus (SLE), describe frequency-specific hearing threshold changes in this patient population as compared to age-matched control, and compare the clinical and serological profiles of patients with SLE with and without HL.

METHODS

A systematic review querying four databases (PubMed, Web of Science, Scopus, and Cochrane) was performed. Meta-analysis of available data was performed to determine the overall prevalence and odds ratio (OR) of HL, and compare mean differences in frequency-specific hearing thresholds between patients with SLE and control. Additionally, meta-analysis of proportions allowed for comparison of disease features present in patients with SLE with and without sensorineural HL.

RESULTS

This review included 17 studies reporting on 1326 patients (635 with SLE and 691 control). The pooled prevalence of HL in patients with SLE was 27%. In comparison to control, patients with SLE had a significantly higher odds of HL (OR 14.6, 95% CI: 8.5 to 25.0). Mean air-conduction hearing thresholds in patients with SLE were significantly elevated relative to control at 125 and 250 Hz. Mean bone-conduction hearing thresholds were significantly elevated in patients with SLE across all measured frequencies except at 3000 and 6000 Hz compared to control. Disease features did not significantly differ between patients with SLE with and without HL.

CONCLUSION

Compared to age-matched control, patients with SLE have increased odds of HL, which primarily manifests at low frequencies. Therefore, this patient population requires greater audiologic attention.

Hearing Loss in Patients With Ankylosing Spondylitis: A Systematic Review and Metaanalysis

OBJECTIVE

To determine the prevalence of hearing loss (HL) in patients with ankylosing spondylitis (AS) and to describe frequency-specific hearing threshold changes in this patient population compared to patients without AS.

METHODS

A systematic review querying 4 databases (PubMed, OVID Medline, Scopus, Cochrane) was performed to identify studies evaluating HL in patients with AS. Metaanalysis was performed to identify overall prevalence rate and OR of HL, as well as to compare mean differences in frequency-specific hearing thresholds between patients with and without AS.

RESULTS

Our metaanalysis included 14 studies and 1083 patients (598 with AS vs 485 without AS). The pooled prevalence of HL in patients with AS was 42.4% (95% CI 29.2-56.2). Patients with AS had a significantly higher OR of HL than patients without AS (OR 4.65, 95% CI 2.73-7.91). Mean differences in pure-tone hearing thresholds ranged from 0-5 decibels (dB) for frequencies of 0.25-4 kHz, and from 5-15 dB for frequencies of 6-16 kHz.

CONCLUSION

Patients with AS have higher odds of having HL than patients without AS. The AS population also presents with significantly impaired hearing thresholds across all conventional and extended pure-tone frequencies. This may manifest as slight to moderate HL. Results of this systematic review might justify increased attention to audiologic manifestations of patients with AS.

Autoimmune Inner Ear Disease among Patients with Selective IgA Deficiency

OBJECTIVES

Autoimmune inner ear disease (AIED) is a distinct clinical entity from sudden sensorineural hearing loss. The purpose of this study was to investigate the clinical characteristics of AIED in patients with selective IgA deficiency (sIgAD).

MATERIALS AND METHODS

This retrospective observational study was based on data from the Leumit Healthcare Services database in Israel. We searched all subjects aged ≥12 years who had undergone serum total IgA measurements during 2004-2014 for any reason. The sIgAD patients included all subjects with serum IgA of ≤7 mg/dL (0.07 g/L). A control group was randomly sampled from the full study population (n ≈ 730,000) with a case-control ratio of 10 controls for each case (1:10).

RESULTS

Among 347 subjects with sIgAD, we identified 9 patients with concomitant AIED (sIgAD + AIED group). This group was characterized by a higher prevalence of allergic diseases (8 patients; 88.9%) than sIgAD patients without AEID (sIgAD + AIED group; 153 patients; 45.2%; p = 0.014). Both systemic diseases (3 patients; 33.3%) and organ-specific autoimmune diseases (7 patients; 77.8%) were more prevalent in the sIgAD + AIED group (sIgAD + AIED group: 19 patients 5.5%, p = 0.015; sIgAD - AEID group: 76 patients, 21.9%, p < 0.001), with an OR of 8.39 (1.94-36.19; p = 0.004). sIgAD patients with and without AIED were characterized by a higher prevalence of documented episodes of acute otitis media, allergic diseases, and autoimmune diseases than the control group.

CONCLUSION

The study exposes a significant association between AIED and sIgAD. We believe that sIgAD has to be excluded in AIED patients.

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.

Effects of familial Mediterranean fever on the middle ear

OBJECTIVE

To evaluate middle and inner ear function and hearing status of children with familial Mediterranean fever (FMF).

METHODS

We assigned 56 patients with FMF to the study group and 52 healthy volunteers to the control group. The mean age of patients in the study and control groups were 10.10 ± 3.70 and 9.77 ± 3.74 years, respectively. Physical examination and hearing evaluation were performed in both groups. The audiological test battery included 226-Hz tympanometry, pure tone audiometric evaluation, acoustic stapedial reflex measurements, distortion product otoacoustic emission recording, and wide-band tympanometry assessment.

RESULTS

The groups were similar in age and sex ratio (p > 0.05 for both comparisons). Pure tone audiogram and distortion product otoacoustic emission results were also similar for both groups (p > 0.05). The ipsilateral acoustic stapedial reflex were present in both of the groups and all participants had Type A tympanogram. The contralateral acoustic stapedial reflex thresholds were significantly higher in the familial Mediterranean fever group (p < 0.05 for all comparisons). The ambient and peak pressure absorbance values of wide-band tympanometry were significantly lower at 2000 Hz and significantly higher at 4000 Hz in the familial Mediterranean fever group (p < 0.05 for both comparisons). The severity and duration of disease adversely affected the absorbance values of wide-band tympanometry at 2000 and 4000 Hz (p < 0.05).

CONCLUSION

To our knowledge, this is the first study to demonstrate the adverse subclinical effects of familial Mediterranean fever on the middle ear. We recommend that children diagnosed with FMF should be closely monitored for future clinical middle ear pathologies.

Antioxidant Therapy against Oxidative Damage of the Inner Ear: Protection and Preconditioning

Oxidative stress is an important mechanism underlying cellular damage of the inner ear, resulting in hearing loss. In order to prevent hearing loss, several types of antioxidants have been investigated; several experiments have shown their ability to effectively prevent noise-induced hearing loss, age-related hearing loss, and ototoxicity in animal models. Exogenous antioxidants has been used as single therapeutic agents or in combination. Antioxidant therapy is generally administered before the production of reactive oxygen species. However, post-exposure treatment could also be effective. Preconditioning refers to the phenomenon of pre-inducing a preventative pathway by subtle stimuli that do not cause permanent damage in the inner ear. This renders the inner ear more resistant to actual stimuli that cause permanent hearing damage. The preconditioning mechanism is also related to the induction of antioxidant enzymes. In this review, we discuss the mechanisms underlying antioxidant-associated therapeutic effects and preconditioning in the inner ear.

Autoimmune inner ear disease patient-associated 28-kDa proinflammatory IL-1β fragment results from caspase-7-mediated cleavage in vitro

Interleukin-1β (IL-1β) is a key proinflammatory cytokine involved in the progression of many autoinflammatory and autoimmune diseases, including autoimmune inner ear disease (AIED). IL-1β inhibition has been shown to result in clinical hearing improvement in a small cohort of corticosteroid-resistant patients with AIED. Canonical processing of pro-IL-1β by caspase-1 generates an active 17-kDa fragment, capable of instigating a proinflammatory microenvironment. However, in response to LPS, PBMCs from patients with AIED uniquely express a 28-kDa IL-1β fragment, as compared with PBMCs from control subjects. We synthesized and compared the biologic activity of the 28-kDa fragment to the 17-kDa IL-1β product and the pro-IL-1 31-kDa protein. The 28-kDa IL-1β fragment induces IL-6, TNF-α, and CCL3 in PBMCs. Uniquely, only caspase-7 treatment showed a dose- and time-dependent increase in 28-kDa band generation. Mass spectrometry confirmed the putative caspase-7 cleavage site of pro-IL-1β, which was used to generate the 28-kDa fragment used for PBMC stimulation studies. Collectively, these results provide insight into the function of a poorly understood, processed 28-kDa form of IL-1β in patients with AIED that is uniquely generated by caspase-7 and is capable of activating further downstream proinflammatory cytokines. Further investigation may provide novel pharmacologic targets for the treatment of this rare disease.