Allergy and Its Relation to Meniere's Disease

Allergy and autoinflammation drive persistent systemic inflammatory response in Meniere Disease: A longitudinal study

BACKGROUND

Meniere disease (MD), an inner ear disorder influenced by genetic and environmental factors, potentially leads to chronic inflammation. This study evaluates whether inflammation in MD patients is driven by allergy or autoinflammation.

METHODS

2-year longitudinal study. Cytokine and chemokine levels were measured in plasma from 72 patients. Functional clusters were identified using weighted-based discriminant and km3d trajectory analyses. THP-1 cells were exposed to patients' plasma to assess macrophage polarization, and qPCR analyzed upstream cytokine release events.

RESULTS

Four groups were identified: 1) Autoimmune (20 %) with high TNF-α (p = 0.0004); 2) Allergic (25 %) with elevated IgE (p < 0.0001) and M2 polarization; 3) Autoinflammatory (13 %) with increased IL-1β (p < 0.0001), activated via CASP1/NLRP3; 4) Low cytokine levels (42 %; cytokines in Q1). Group stability was observed, with 36 % of allergic patients also showing high IL-1β.

CONCLUSION

Identified immunophenotypes, allergy-driven IgE responses, and IL-1β-mediated autoinflammation indicate that targeting inflammation with biomarkers could optimize MD treatment and outcomes.

Allergic diseases and Meniere's disease: a bidirectional Mendelian randomization

OBJECTIVES

Allergic diseases and Meniere's disease found to have a possible link in observational study. However, the potential causal relationship between the two is unclear. Therefore, we aimed to explore the causal relationship between allergic diseases and Meniere's disease using a new data analysis technique called bidirectional Mendelian randomization study.

METHOD

Summary-level statistics for Meniere's disease and three allergic diseases (asthma, allergic rhinitis, eczema/dermatitis) were obtained from large-scale genome-wide association studies. The inverse variance weighted method was used as the primary measure, supplemented by MR-Egger regression and the weighted median method. To ensure the reliability of the conclusions, Cochran's Q, MR-Egger intercept, MR-PRESSO test, leave-one-out test, and MR Steiger test were used.

RESULTS

Inverse-variance weighted method showed asthma (p = 0.008, OR = 3.908, 95% CI 1.424-10.724, adjust_p = 0.024), allergic rhinitis (p = 0.026, OR = 24.714, 95% CI 1.479-412.827, adjust_p = 0.026) and eczema/dermatitis (p = 0.019, OR = 3725.954, 95% CI 3.795 to 3,658,399.580, adjust_p = 0.029) all had a significant effect on Meniere's disease. Reverse Mendelian randomization studies have shown that Meniere's disease does not increase the risk of three allergic diseases. Sensitivity analysis showed no horizontal pleiotropy and heterogeneity for each trait.

CONCLUSION

Our Mendelian randomization analysis supports a positive causal relationship between three allergic diseases (asthma, allergic rhinitis, eczema/dermatitis) and Meniere's disease. This suggests that physicians should pay more attention to the Meniere's patient's allergy history and consider allergy avoidance as part of their treatment plan.

LEVEL OF EVIDENCE

Mendelian Randomized (MR) studies are second only to randomized controlled trials in terms of the level of evidence.

Betahistine's Neuroprotective Actions against Lipopolysaccharide-Induced Neurotoxicity: Insights from Experimental and Computational Studies

Histamine H3 receptor (H3R) antagonists, such as betahistine (BHTE), have shown significant potential in treating central nervous system (CNS) disorders due to their neuroprotective properties. This study investigated BHTE's effects on lipopolysaccharide (LPS)-induced neurotoxicity, which is associated with neuroinflammation and neurodegeneration. Rats were divided into groups and pre-treated with BHTE (5 or 10 mg/kg, p.o.) for 30 days, followed by LPS administration (1 mg/kg, i.p.) for 4 consecutive days to induce neurotoxicity. LPS exposure resulted in cognitive impairment, as evidenced by performance deficits in maze tests, and a significant reduction in brain acetylcholine (ACh) levels. Additionally, LPS led to increased neuroinflammation, oxidative stress, mitochondrial dysfunction, and apoptosis. Pre-treatment with BHTE effectively counteracted these effects, improving cognitive performance and restoring ACh levels. BHTE significantly reduced LPS-induced increases in pro-inflammatory markers (COX-2, TNF-α, and IL-6) while enhancing anti-inflammatory cytokines (IL-10 and TGF-β1). Furthermore, BHTE improved mitochondrial function by increasing enzyme levels (MRCC-I, II, and IV) and boosted anti-apoptotic (Bcl-2) and antioxidant defenses (GSH and catalase). BHTE also reduced apoptosis markers, including pro-apoptotic protein caspase-3, and oxidative stress marker malondialdehyde (MDA). Molecular modeling studies revealed that BHTE effectively binds to key enzymes involved in neuroinflammation and apoptosis (AChE, COX-2, and caspase-3), with binding free energies between 4 and 5 kcal/mol, interacting with critical residues. These findings underscore BHTE's multifaceted neuroprotective effects against LPS-induced neurotoxicity, offering potential therapeutic avenues for managing neuroinflammation and related neurodegenerative disorders.

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.

Ménière's disease and allergy: Epidemiology, pathogenesis, and therapy

The etiology of Ménière's disease (MD) remains controversial. Allergies are potential extrinsic factors that, in conjunction with underlying intrinsic factors, may cause MD. The link between allergies and MD was first described in 1923. For nearly a century, studies have demonstrated a possible link between allergies and MD, even though a causal relationship has not been definitively determined. Previous reviews have mainly focused on clinical epidemiology studies of patients. In this review, we shed light on the association between allergies and MD not only in terms of its epidemiology, but also from an immunology, pathophysiology, and immunotherapy perspective in both patients and animal models. Patients with MD tend to have a high risk of comorbid allergies or an allergy history, showing positive allergy immunology characteristics. Other MD-related diseases, such as migraine, may also interact with allergies. Allergy mediators such as IgE may worsen the symptoms of MD. Deposits of IgE in the vestibular end organs indicate the ability of the inner ear to participate in immune reactions. Allergic challenges can induce vertigo in animals and humans. Anti-allergy therapy plays a positive role in patients with MD and animal models of endolymphatic hydrops.

Protective effect of anakinra on audiovestibular function in a murine model of endolymphatic hydrops

Introduction

Ménière's disease (MD), a common disease in the inner ear, is characterized by an increase in endolymph in the cochlear duct and vestibular labyrinth. The pathophysiology of the condition appears to be the immune response. Studies have shown that basal levels of the IL-1β increased in some MD patients.

Methods

Here, we used a murine model of endolymphatic hydrops (EH) to study the effect of anakinra on auditory and vestibular function. Mice were intraperitoneal injected with anakinra or saline before LPS by postauricular injection. Weight and disease severity were measured, histologic changes in auditory were assessed, and inflammation state was evaluated.

Results

We found that anakinra therapy reduced LPS-induced EH, alleviated LPS-induced hearing loss and vestibular dysfunction, and inhibited the expression of the inflammatory cytokines and macrophage infiltration in the cochlea of mice. We further demonstrated that anakinra ameliorated the disorganization and degeneration of myelin sheath, and reduced the neuron damage in cochlea of EH mice.

Discussion

Consequently, anakinra contributes to a promising therapeutic approach to MD, by restricting EH, alleviating auditory and vestibular function, inhibiting inflammation of the inner ear and protecting the cochlear nerve. Further investigations are needed to assess the potential therapeutic benefits of anakinra in patients with MD.

Pathogenesis and Etiology of Ménière Disease: A Scoping Review of a Century of Evidence

IMPORTANCE

Ménière disease is a rare chronic benign disorder of the inner ear with a natural history of multiple clinical phenotypes of variable severity and a tendency to burnout with time. Although multiple treatment modalities have been shown to improve the disease process-some adversely affecting cochleovestibular function-it remains uncertain whether one, several separate, or a combination of pathophysiologic mechanisms affect the disease process. A scoping review of the evidence underlying proposed pathophysiologic mechanisms of Ménière disease is needed to determine which processes are most likely to be etiopathogenic factors.

OBSERVATIONS

Of the 4602 relevant articles found through Embase, Ovid, and PubMed, 444 met inclusion criteria. The most common reported causes of Ménière disease were autoimmune or immune-mediated, genetic, or structural dysfunction of the inner ear. During the study period from inception to March 2021, etiologic theories shifted from structural dysfunction to autoimmune and genetic causes of Ménière disease.

CONCLUSIONS AND RELEVANCE

This scoping review found that Ménière disease is a multifactorial disease with lifelong comorbidities and loss of quality-associated life-years whose most commonly reported causes were structural dysfunction, immunologic damage, and genetic susceptibility. Recent studies have examined how autoinflammatory processes and vestibular migraine may be associated with Ménière disease. Large heterogeneity among studies may be explained by historical differences in the clinical understanding of the disease, as well as evolving intervention methodologies and practitioner expertise. Ménière disease is a multifactorial disease with lifelong comorbidities and loss of quality-associated life-years; therefore, future studies of reliable biomarkers of endolymphatic hydrops and real-time imaging are warranted to improve understanding and treatment.

Bidirectional Transport of IgE by CD23 in the Inner Ear of Patients with Meniere's Disease

Meniere's disease (MD) is a disorder of the inner ear characterized by episodes of spontaneous vertigo, fluctuating hearing loss, and tinnitus. Recent studies have demonstrated that IgE may play a role in the pathogenesis of MD. Patients with MD (n = 103), acoustic neuroma (n = 5), and healthy subjects (n = 72) were recruited into the study. Serum from the participants was analyzed for IgE and type 2-related cytokines. IgE and CD23 expression levels in vestibular end organs of patients, C57BL/6 mice, or mouse HEI-OC1 cells were analyzed. Finally, the role of CD23 in IgE transcytosis was assessed using HEI-OC1 cells. Serum IgE was elevated in patients with MD and positively correlated with clinical symptoms. IL-4, IL-5, IL-10, IL-13, and CD23 levels were increased in patients with MD compared with the control group. In the transcytosis assay, mouse IgE was found to be bidirectionally transported across the HEI-OC1 cell monolayer. Additionally, CD23 downregulation using a small interfering RNA approach significantly reduced the efficiency of IgE transcytosis, suggesting that IgE is transported by CD23. Furthermore, exposure to IL-4 increased CD23 expression and enhanced IgE transcytosis in the HEI-OC1 cells and primary vestibular end organs. Our study indicated that IgE may play a role in the pathophysiology of MD. In addition, CD23-mediated IgE transcytosis in the hair cells may play a critical role in initiating inflammation in the inner ear. Thus, reducing the level of IgE may be a potentially effective approach for MD treatment.

Cyclophosphamide inhibits the progression of Meniere's disease by reducing the generation of circulating immune complex

Endolymphatic hydrops is a characteristic pathological manifestation of Meniere's disease (MD) that has been previously associated with autoimmunity. Interest in the circulating immune complex (CIC) has increased due to its reported role in the occurrence of MD. The present study aimed to investigate the potential value of serum CIC concentration in the diagnosis of MD and the therapeutic potential of cyclophosphamide (CTX) for the treatment of MD. In the present study, guinea pigs were immunized with isologous crude inner ear antigens to establish an autoimmune MD model. Pure tone audiometry, Vestibular-evoked myogenic potential test, electrocochleography test and auditory brainstem response was applied in this study for assessing the severity of MD in guinea pigs. ELISA was applied to measure CIC, tumor necrosis factor α (TNF-α) and heat shock protein 70 (HSP70) expression levels in the serum samples of different groups of patients. Western blotting was applied to detect the protein expression of HSP70 in inner ear tissues in guinea pigs. Hematoxylin and eosin staining was applied to visualize the spiral ganglions in spiral ganglions models. CIC expression in the inner ear was detected by immunohistochemistry. In vivo experiments were performed to confirm the therapeutic effects of CTX in MD. Serum concentrations of CIC, TNF-α and HSP70 were found to be significantly higher in patients with MD, which were also associated with increases in hearing classification and the severity of endolymphatic hydrops. Using a guinea pig MD model, ELISA results revealed significantly increased serum CIC, TNF-α and HSP70 concentrations compared with those in the control group. ABR results showed that the thresholds in the CTX group were notably decreased compared with that in the dexamethasone group, whereas CIC concentrations in the serum were reduced following dexamethasone and CTX treatments compared with those after saline treatment. In the inner ear tissues, the CIC concentration in CTX group was lower than that in the dexamethasone group. Similarly, reductions in HSP70 and TNF-α concentrations was also observed in a similar manner. Immunohistochemistry staining found notably lower CIC deposition in the inner ear tissues following CTX treatment than that in dexamethasone group. Taken together, higher CIC expression can be used as a biomarker for MD diagnosis. The efficacy of CTX in MD was found to be higher compared with that in dexamethasone, which may be associated with the effective inhibition of CIC, HSP70 and TNF-α generation.

Allergy, Immunotherapy, and Alternative Treatments for Dizziness

Allergic reactions may result in central symptoms of dizziness, including nonspecific chronic imbalance, Meniere's disease, and autoimmune inner ear disease. Excepting first-generation antihistamines, and short-term use of steroids, most pharmacotherapies used to treat allergic rhinitis have limited benefit in treating allergically induced or related dizziness. Allergy immunotherapy and/or an elimination diet for diagnosed food allergies have been found to be effective treatments. Individuals diagnosed with autoimmune inner ear disease remain challenging to treat and may require high-dose, long-term steroid treatment, biologics, or immunomodulators for symptom control.

The relationship between nutrition and Ménière's disease

Ménière's disease is an inner ear disease with attacks characterized by ear fullness, tinnitus, fluctuant sensorineural hearing loss and vertigo. Although pathophysiology of the disease is not fully known, endolymphatic hydrops are believed to play a role. Although there is no certain treatment procedure for Ménière's disease, some treatments are applied to prevent attacks, to treat the symptoms that occur during the attacks, and to prevent the permanent effects of the symptoms on the hearing and balance system. Lifestyle changes, dietary modifications, diuretics, vasodilator corticosteroids, intratympanic steroids, surgical methods are some of these treatment methods. Dietary modification includes a low sodium diet, a reduction in daily alcohol and caffeine intake, a gluten-free diet, and a new dietary approach to specially processed grains, all of which are first-line treatments. The goal of this review article is to examine the relationship between MD and dietary intervention, which is frequently used in the prevention and treatment of MD attacks.

Evaluation of Serum Immunoreactivity to Common Indigenous Iranian Inhalation and Food Allergens in Patients with Meniere's Disease

Background: A few studies investigated the relationship between allergy and Meniere disease considering complete allergen panel. We aimed to evaluate the serum immunoreactivity in patients with Meniere's disease (MD) compared with healthy people according to common indigenous Iranian inhalation and food allergens.Methods: Thirty-nine patients with MD referred to Rasoul Akram Hospital (Tehran, Iran) were evaluated and compared with a 41 membered control group. A panel of common inhalation and food allergens (using an immunoblotting method), as well as total immunoglobulin E (IgE) level (using the sandwich enzyme-linked immunosorbent assay method), were checked on the patients' serum.Results: The mean total IgE level was 193.85 ± 175.43 IU/ml in the patients with MD and 117.61 ± 138.05 IU/ml in the control group, which was significantly higher than the other subjects in the control group (P = .016). There was a significant difference between the two groups regarding inhalation allergens such as; sweet vernal grass, cultivated rye, cultivated oat, Russian thistle, goosefoot, and rough pigweed (P = .01-0.038). Patients with MD reported more reactive to food allergens such as; rye flour, hazelnut, pepper, citrus mix 2, potato, strawberry, and celery allergens. There was a significant relationship between Meniere and serum immunoreactivity to inhalation and food allergens (both P = .001).Conclusion: Serum total IgE level in patients with MD (in both inhalation and food allergens groups) was higher than the control group, and there was a relationship between MD and immunoreactivity to common indigenous inhalation and food allergens of Iran.

The Atopy Index Inventory: A Brief and Simple Tool to Identify Atopic Patients

INTRODUCTION

Atopy and ear, nose and throat (ENT) diseases are frequently associated; however, no clinical tool has been proposed so far to discriminate which patients could be atopic and therefore deserving of a further immunoallergological evaluation.

OBJECTIVE

The aim of this study was to assess and validate a set of dichotomous responses suitable for predicting the presence of atopy in adult patients.

METHODS

An 11-item questionnaire, i.e., the Atopy Index Inventory (AII), comprised of 4 questions regarding the clinical history for allergic disease and 7 questions evaluating the presence of the most frequent clinical signs affecting allergic patients, was developed and administered to 226 adult subjects (124 atopic subjects and 102 healthy, not atopic subjects). The atopic condition was proven by an immunoallergological evaluation according to the diagnostic criteria of the EAACI guidelines. Internal consistency and clinical validity were tested.

RESULTS

In healthy subjects, the first 4 variables of the AII returned a 100% correct response (all answered "no") and were defined as "decisive" responses. In the logistic regression analysis, when decisive items were negative, the atopic condition was confirmed when answering "yes" to at least 3 "probability" items (cut-off = 2.69). The difference in AII scores between allergic and healthy group was significant using the Mann-Whitney U test (p < 0.0001). The sensitivity and specificity of the AII were 0.97 and 0.91, respectively, with a true predictive value of 0.92 and a false predictive value of 0.97. The ROC curve showed an area of 0.94, with an OR of 0.88 (95% CI 0.87-0.97, p = 0.0001). The internal consistency as determined by the Cronbach α coefficient was 0.88.

CONCLUSION

The AII has been proven to be a brief, simple and sufficiently accurate tool for screening ENT patients in search of atopic individuals and to allow their clinical management.

A comparison of endolymphatic shunt surgery and intratympanic gentamicin for meniere's disease

OBJECTIVE

To report audiovestibular outcomes following endolymphatic shunt surgery (ELS) and intratympanic gentamicin injections (ITG) in patients with Meniere's disease (MD).

STUDY DESIGN

Retrospective matched cohort study METHODS: Patients with MD refractory to medical management between 2004 and 2017 were reviewed: 44 patients underwent ELS and had outcomes available, while 27 patients underwent ITG and had outcomes available. Mean follow-up durations for the ELS and ITG groups were 39.1 and 43.3 months, respectively. Twenty-six patients from the ELS group and 24 patients from the ITG group were then included in a pretreatment hearing- and age-matched analysis. Main outcome measures were successful control of vertigo, pure-tone average (PTA; 0.5, 1, 2 and 4 kHz), word recognition score (WRS), and treatment complications.

RESULTS

A matched analysis showed vertigo control rates of 73.1% in the ELS group and 66.8% in the ITG group, which were not significantly different (P = .760). The change in PTA following treatment was statistically similar between the ELS group (6.2 dB) and ITG group (4.6 dB) (P = .521), while the change in WRS for the ELS group (+3.9 %) was significantly more favorable than the ITG group (-13.6 %) (P = .046). Chronic post-treatment unsteadiness was reported in 25.0% of the ITG group and was not encountered in the ELS group (P = .009).

CONCLUSION

ELS provided successful vertigo control at least as well as ITG with a lower incidence of audiovestibular complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2455-2460, 2020.

Are viral-infections associated with Ménière's Disease? A systematic review and meta-analysis of molecular-markers of viral-infection in case-controlled observational studies of MD

Despite considerable research, it remains controversial as to whether viral-infections are associated with Meniere’s Disease (MD), a clinically heterogeneous set of chronic inner-ear disorders strongly associated with endolymphatic hydrops. Here, we investigated whether viral-infections are associated with MD through a systematic review and meta-analysis of observational clinical studies using molecular-diagnostics. Eligible for inclusion were case-controlled studies which ascertained molecular-determinants of past or present viral-infection through either viral nucleic acids or host serological marker in MD cases and non-MD controls. Across online databases and grey literature, we identified 210 potentially relevant articles in the English language, from which a total of 14 articles fully satisfied our eligibility criteria such that meta-groups of 611 MD-cases and 373 controls resulted. The aggregate quality of the modest-sized (14 studies) body of evidence was limited and varied considerably with regards to participant selection, matching, and ascertainment(s) and determinant(s) of viral-infection. Most data identified concerned the human cytomegalovirus (CMV), and meta-analysis of eligible studies revealed that evidence of CMV-infection was associated approximately three-fold with MD compared to controls, however the timing of the infections was indeterminate as the pooled analyses combined antiviral serological markers with viral nucleic acid markers. No association was found for any of HSV-1, -2, VZV, or EBV. Associative analyses of any viral species not aforementioned were precluded by limited data, and thus potential associations between other viral species and MD, especially other than Herpesviridae, are yet to be characterised. Overall, we have found a small association between CMV-infection and MD, however it is to be determined for what sub-groups of MD this finding may be relevant, and ideally the reported association remains would be reproduced by a greater volume of higher quality evidence.

Gadolinium-enhanced MRI reveals dynamic development of endolymphatic hydrops in Ménière's disease

INTRODUCTION

Meniere's disease is associated with impaired hearing, tinnitus, vertigo, and aural fullness. Many anatomical studies have suggested idiopathic endolymphatic hydrops as the pathological basis of Meniere's disease, which now can be visualized by using gadolinium -enhanced magnetic resonance imaging of the inner ear.

OBJECTIVE

To investigate the development of endolymphatic hydrops in Meniere's disease by monitoring the vestibules and cochleae of affected patients.

METHODS

Inner ears of 178 patients with definite unilateral Meniere's disease diagnosis were visualized by 3-dimensional fluid-attenuated inversion recovery and three-dimensional real inversion recovery magnetic resonance imaging following bilateral gadolinium intratympanic injection. The scans were used to evaluate the presence and degree of endolymphatic hydrops in the vestibules and cochlear structures, including the cochlear apical turn, the cochlear middle turn, and the cochlear basal turn. The correlation of endolymphatic hydrops occurrence between the various parts of the inner ear was determined.

RESULTS

Symptomatic endolymphatic hydrops was detected on the affected side in all patients, whereas asymptomatic endolymphatic hydrops was detected on the unaffected contra-lateral side in 32 patients (18.0%). On the affected side, the cochlear apical turn and the cochlear middle turn demonstrated significantly higher rates of endolymphatic hydrops than the cochlear basal turn and the vestibule. The severity of endolymphatic hydrops gradually decreased from the cochlear apical turn to the cochlear basal turn. On the contra lateral side, the incidence and degree of the detected asymptomatic endolymphatic hydrops were significantly greater in the cochleae than in the vestibules (p<0.05), with no significant difference detected between the cochlear turns.

CONCLUSION

Progression of endolymphatic hydrops appears to be directional, initiated in the cochlea. The order of endolymphatic hydrops severity gradually decreases from the cochlear apical turn to the cochlear basal turn and then to the vestibule. Endolymphatic hydrops in the vestibule is associated with symptomatic Meniere's disease.

The aetiopathologies of Ménière's disease: a contemporary review

Ménière's disease, a condition first described in the 1800's, has been an advancing area of clinical interest and scientific research in recent decades. Guidelines published by the American Academy of Otolaryngology - Head and Neck Surgery remained nearly static for almost 20 years, although we have certainly expanded our knowledge of the aetiology of the disease since that time. This review of the literature highlights the breadth and detail of the current theories in understanding the pathophysiology of this enigmatic disease. Histopathological specimens providing evidence of many of the aetiologies are presented as well. We aim to provide a centralised and updated resource regarding current and emerging theories for Ménière's disease.

Stress and Unusual Events Exacerbate Symptoms in Menière's Disease: A Longitudinal Study

HYPOTHESIS

Stress and unusual events are associated with a higher likelihood of attacks and increased symptom severity in Menière's disease (MD).

BACKGROUND

MD is an unpredictable condition which severely impacts the quality of life of those affected. It is thought that unusual activity and stress may act as an attack trigger in MD, but research in this area has been limited to date.

METHODS

This was a longitudinal study conducted over two phases. A mobile phone application was used to collect daily data on Menière's attacks and individual symptoms (aural fullness, dizziness, hearing loss, and tinnitus), as well as prevalence of unusual events (phase I), and stress levels (phase II). There were 1,031 participants (730 women, mean age 46.0 yr) in phase I and 695 participants (484 women, mean age 47.7 yr) in phase II. Panel data regression analyses were employed to examine for associations between unusual events/stress and attacks/symptoms, including the study of 24 hours lead and lag effects.

RESULTS

Unusual events and higher stress levels were associated with higher odds of Menière's attacks and more severe symptoms. The odds of experiencing an attack were 2.94 (95% confidence interval [CI] 2.37, 3.65) with reporting of unusual events and increased by 1.24 (95% CI 1.20, 1.28) per unit increase in stress level. Twenty-four hour lead (OR 1.10 [95% CI 1.07, 1.14]) and lag (OR 1.10 [95% CI 1.06, 1.13]) effects on attacks were also found with increases in stress.

CONCLUSION

This study provides the strongest evidence to date that stress and unusual events are associated with attacks and symptom exacerbation in MD. Improving our understanding of stress and unusual events as triggers in Menière's may reduce the uncertainty associated with this condition and lead to improved quality of life for affected individuals.

Intestinal permeability and Ménière's disease

PURPOSE

Ménière disease (MD) is a multifactorial chronic disabling condition characterized by episodic vertigo, ear fullness, and hearing loss. MD patients often complain of aspecific gastrointestinal symptoms associated with autonomic dysregulation, frequently outweighed by the otological manifestations. Dietary modifications have been reported to improve the typical MD symptoms in some cases. Our purpose was to test the urinary levels of lactulose and mannitol (double sugar test) and the fecal calprotectin, both markers of altered intestinal permeability, in subjects with definite MD in an active and inactive stage.

MATERIALS AND METHODS

Twenty-six with definite unilateral MD were studied: 14 patients were symptomatic for at least 3months with moderate to severe vertigo spells and a functional level ≥4; 12 patients had been asymptomatic (no vertigo spells) for at least 3months and had a functional level=1 at the time of testing. Twenty healthy volunteers were recruited as "control group".

RESULTS

Lactulose and mannitol absorption was significantly increased in the symptomatic M patients compared to the asymptomatic group (p<0.02 and p<0.004, respectively) and to the controls. FC were also higher than normal only in the symptomatic group. (p<0.01).

CONCLUSIONS

An altered intestinal permeability, according to the two assays, was found only in symptomatic MD patients. The rationale for a possible relationship between MD and intestinal permeability is forwarded. The double-sugar test and FC quantification might be implemented in the MD diagnostic workup.

Delayed Immunomodulatory Effect of Cow Milk-Free Diet in Ménière's Disease

OBJECTIVE

Since 1930, dietary modification has been proposed as adjunct treatment in Ménière's disease (MD) with different and controversial results. We report the case of a 42-year-old female suffering from definite MD and intermittent seasonal allergic rhino-conjunctivitis because it highlights the importance of evaluating the different combinations of defined causative elements in an atopic patient with MD.

METHODS

An immunological and audiological evaluation was performed, including pure-tone, speech, and immittance audiometry; glycerol dehydration test; bithermal caloric testing; video head impulse test; cervical vestibular evoked myogenic potentials; static posturography; and Dizziness Handicap Inventory questionnaire.

RESULTS

A milk-free diet was crucial to relief from MD symptoms and a cow's milk challenge test was able to evoke them but vestibukar symptoms persist.

CONCLUSIONS

The effect of dietary modification was evident only after specific immunotherapies against other allergens. This highlights the importance of evaluating different combinations of defined causative elements in the allergic treatment of MD.

The Role of Allergy in Otologic Disease

Allergy is commonly associated with conditions such as rhinitis, sinusitis, and asthma, but the relationship between allergy and otologic diseases is less clear. This article examines the evidence for a relationship between allergic disease and several common otologic conditions, including otitis media with effusion, eosinophilic otitis media, and Ménière's disease.

A network-based method using a random walk with restart algorithm and screening tests to identify novel genes associated with Menière's disease

As a chronic illness derived from hair cells of the inner ear, Menière’s disease (MD) negatively influences the quality of life of individuals and leads to a number of symptoms, such as dizziness, temporary hearing loss, and tinnitus. The complete identification of novel genes related to MD would help elucidate its underlying pathological mechanisms and improve its diagnosis and treatment. In this study, a network-based method was developed to identify novel MD-related genes based on known MD-related genes. A human protein-protein interaction (PPI) network was constructed using the PPI information reported in the STRING database. A classic ranking algorithm, the random walk with restart (RWR) algorithm, was employed to search for novel genes using known genes as seed nodes. To make the identified genes more reliable, a series of screening tests, including a permutation test, an interaction test and an enrichment test, were designed to select essential genes from those obtained by the RWR algorithm. As a result, several inferred genes, such as CD4, NOTCH2 and IL6, were discovered. Finally, a detailed biological analysis was performed on fifteen of the important inferred genes, which indicated their strong associations with MD.

Association between ambient particulate matter and disorders of vestibular function

BACKGROUND

Exposure to environmental chemicals has been suggested to alter the physiologic state of the inner and middle ear. However, it is unknown if particulate matter exposure is associated with acute vestibular dysfunction.

OBJECTIVES

To estimate the effects of particulate matter exposure on the number of hospital visits related to three major diseases of vestibular dysfunction, Meniere's disease (MD), benign paroxysmal positional vertigo (BPPV), and vestibular neuronitis (VN).

METHODS

Our study subject is from Korean National Health Insurance Service-National Sample Cohort, which is dynamic cohort consist of 1 million participants representing the Korean population. Among total cohort participants, we used the hospital visit data of 210,000 individuals who resided in Seoul from 2007 to 2010. Time series analysis using the Poisson generalized additive model and case-crossover analysis using conditional logistic regression were used to investigate the association between daily particulate matter levels (PM_2.5, particulate matter <2.5μg/m³; PM₁₀, particulate matter <10μg/m³; PM_10-2.5, PM₁₀- PM_2.5) and number of MD, BPPV, and VN hospital visits.

RESULTS

Time series analysis showed that an interquartile range (IQR) increase in PM₁₀ and PM_10-2.5 on lag day 1 was associated with an increased risk of MD hospital visits [relative risk (RR), 95% confidence interval (CI), PM₁₀: 1.09 (1.02-1.15); PM_10-2.5: 1.06 (1.02-1.10)]. In addition, elderly individuals (≥60 years old) showed an increased risk of MD hospital visits after particulate matter exposure when compared to younger individuals. An IQR increase in particulate matter on lag day 1 was associated with a marginally significant increase in VN hospital visits [RR (95%CI), PM_2.5: 1.11 (0.98-1.25); PM₁₀: 1.07 (0.99-1.15); PM_10-2.5: 1.04 (0.99-1.09)]. However, no association between particulate matter exposure and BPPV hospital visits was noted. Case-crossover analyses showed similar results to the time-series analysis across all three diseases.

CONCLUSION

MD hospital visits were associated with ambient particulate matter exposure. Elderly individuals, in particular, were more susceptible to particulate matter exposure than younger individuals.

Menière's disease

Menière's disease (MD) is a chronic multifactorial disorder of the inner ear characterized by episodic vestibular symptoms associated with sensorineural hearing loss, tinnitus, and aural pressure. Epidemiologic and genomic evidence supports a genetic susceptibility with multiple biochemical pathways involved, including the endocrine system, innate immune response, and autonomic nervous system. Allergens, infectious agents, vascular events, or genetic factors could modify inner-ear homeostasis and trigger MD. The diagnosis of MD is based on clinical criteria and requires the observation of an episodic vertigo syndrome associated with low- to medium-frequency sensorineural hearing loss and fluctuating aural symptoms (hearing loss, tinnitus, and/or fullness) in the affected ear. Headache is also found during the attacks and bilateral involvement is found in 25-40% of cases. Audiologic and vestibular assessment is recommended to monitor the clinical course. The treatment of MD is symptomatic to obtain relief of vestibular episodes and preventive to limit hearing loss progression. Treatment options include sodium restriction, betahistine, intratympanic gentamicin, or steroids and eventually surgery, such as cochlear implantation.

The link between allergy and Menière's disease

PURPOSE OF REVIEW

To examine evidence supporting the association of allergy and Menière's disease.

RECENT FINDINGS

Animal studies have shown evidence that a provoked systemic immune challenge can result in an allergic reaction within the inner ear, whereas premedication with leukotriene antagonists can prevent the development of endolymphatic hydrops. In human subjects, further data support a heightened allergic response in patients with Menière's disease, whereas pharmacological treatments that target histamine receptors help to control vertiginous symptoms. However, the relationship of migraine with a history of allergy and Menière's disease may confound this association.

SUMMARY

Although the evidence of a causal association between allergy and Menière's disease is inconclusive, the inclusion of allergy control as part of the treatment plan for Menière's disease is low risk to the patient and should be considered for patients with indications that include history of seasonal or food allergy, childhood or family history of allergy, bilateral Menière's symptoms, or a development of symptoms within a short time after exposure of food or inhaled allergen.

Oral steroid treatment for hearing improvement in Ménière's disease and endolymphatic hydrops

OBJECTIVE

To determine the effect of oral steroid treatment on hearing in unilateral Ménière's disease and endolymphatic hydrops patients.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary referral center.

PATIENTS

All patients presenting during the 2010 calendar year with confirmed unilateral Ménière's disease or endolymphatic hydrops. Those with a first visit and second visit audiogram (n = 58) were included in the analysis of oral steroid treatment effect.

INTERVENTION

Steroid treatment for hearing loss.

MAIN OUTCOME MEASURE

Change in hearing, as defined by change in affected ear threshold values or speech discrimination score from pretreatment visit to posttreatment visit.

RESULTS

Hearing (threshold, speech discrimination score) in patients' affected ear did not significantly change from first visit to second visit after treatment with steroids relative to patients who did not receive steroid treatment.

CONCLUSION

The results of this and other studies would indicate that a Ménière's disease or endolymphatic hydrops patient is unlikely to experience an improvement in hearing from a short course of oral steroid. Clinically observed temporary improvement did not sustain over several months. Further work to elucidate the mechanisms underlying hearing loss in hydrops, perhaps focusing on the dendrite damage noted in animal models of hydrops, is warranted.

Is allergy related to Meniere's disease?

Meniere's disease (MD) is characterized by episodic rotational vertigo, fluctuating sensorineural hearing loss, aural pressure, and tinnitus. The cause of MD is thought to be multifactorial, with anatomic and genetic contributions. Allergy is thought to be one of the possible extrinsic factors that, when combined with underlying intrinsic factors, may lead to MD. We review the epidemiologic associations of MD and allergy and review the recent literature on the association of allergy and MD.

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.

Gluten sensitivity in Meniere's disease

OBJECTIVES/HYPOTHESIS

Wheat is one of the most common food allergens found in patients with Meniere's disease (MD). Gluten from wheat has been identified to have a etiopathogenetic role in celiac disease, IgE hypersensitivity to wheat disease, and recently to gluten sensitivity. The aim of this study was to verify the incidence of gliadin prick test response in patients affected by MD.

STUDY DESIGN

Prospective individual case-control study.

METHODS

There were 58 adult patients with definite MD, 25 healthy volunteers, and 25 patients with grass pollen rhinoconjunctivitis tested with skin prick test to gliadin.

RESULTS

A total of 33 MD patients (56.9%) proved to be sensitive to gliadin, eight of whom were positive to prick test after 20 minutes, 13 after 6 hours, 11 after 12 hours, and one after 24 hours.

CONCLUSIONS

This is the first report of gliadin skin test response in MD. Further studies are needed to define the relationship between immune response to wheat proteins and MD symptoms.