Patients with Meniére's disease possess IgE reacting with herpes family viruses

Infectious causes and mimickers of meniere's disease

PURPOSE OF REVIEW

To review the evidence of a possible viral etiology of Meniere's disease, the role of antiviral therapy, as well as other infectious disease processes that may mimic Meniere's disease. Better understanding of the etiology of Meniere's disease and the role of various infectious disease processes may allow for more effective diagnosis and management.

RECENT FINDINGS

There is evidence that viral infections - to Herpes simplex virus, cytomegalovirus, Epstein Barr virus, influenza, adenovirus, Coxsackie virus B, and Varicella Zoster Virus - may be involved in the development of Meniere's disease, however the evidence is inconsistent and the underlying mechanism remains theoretical. Nevertheless, antiviral therapy may be effective for a subset of patients with Meniere's disease. Lastly, other infectious diseases including Lyme disease and syphilis can present with symptoms similar to Meniere's disease. It is important to discern these from Meniere's disease to determine the appropriate treatment.

SUMMARY

There is a paucity of high-quality evidence to support a viral etiology of Meniere's disease, and the current evidence appears circumstantial and inconsistent. Additional research is necessary to establish the mechanism and causative pathogens. Antiviral therapy may provide therapeutic benefit for a subset of patients with Meniere's disease. Furthermore, clinicians should be aware of other infectious mimics of Meniere's disease and include them in the differential diagnosis of patients presenting with Meniere's-like symptoms. Research on this subject continues to evolve, and data from these studies represent a growing repository of evidence that can be used to guide clinical decision-making.

The Role of Atopy in COPD and Asthma

Common to several allergic diseases is the generation of immunoglobulin E (IgE) by plasma cells, when exposed to an innocuous antigen. Asthma and chronic obstructive pulmonary disease (COPD) are two prevalent chronic airway inflammatory diseases. Asthma is mediated in some patients through eosinophilic inflammatory mechanisms that include allergic sensitization and Th2-mediated immune airway response. COPD, on the other hand is mainly considered a Th1-mediated inflammatory process with neutrophilic predominance or a non-Th2 inflammation, occasionally associated with the presence of airway bacteria or viruses. IgE production appears to play an important role in the development of both COPD and asthma, as it has been associated to respiratory symptoms, lung function, bacterial and viral infections, airway remodeling and bronchial hyperreactivity in both diseases. The aim of this review is to summarize all current data concerning the role of specific and total IgE in COPD and asthma and to highlight similarities and differences in view of possible therapeutic interventions.

Association between Meniere's disease and air pollution in South Korea

Meniere's disease is thought to be a disorder of the inner ear function, affected by genetic and environmental factors. Several recent studies have shown that air pollution could affect middle and inner ear diseases. The purpose of this study was to investigate the relationship between the Meniere's disease occurrence and air pollution status in Korea. This study used a time-stratified case-crossover design. Hospital visit data by Meniere's disease were collected from the Korea National Health Insurance Service-National Sample Cohort (NHIS-NSC) database. Daily air pollution data for sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and particulate matter (PM10: ≤ 10 μm in diameter, and PM2.5: ≤ 2.5 μm in diameter) were collected from the National Ambient air quality Monitoring Information System (NAMIS) database. We used two-stage analysis to assess the association between degree of air pollution and the occurrence of Meniere's disease. In the first stage, region-specific analysis was conducted to estimate the odds ratios (ORs) of Meniere's disease risk associated with each air pollutant exposure by using conditional logistic regression for matched case-control sets in 16 regions. In the second stage, region-specific ORs from the first stage were combined and the pooled effect estimates were derived through fixed and random effect meta-analysis. Subgroup analysis was conducted for age, sex, seasonality, and urbanization of residence. In total, 29,646 (32.1% males and 67.9% females) Meniere's disease cases were identified from Korea NHIS-NSC database between 2008 and 2015. Overall, SO2, NO2, CO, and PM10 showed significant correlation with Meniere's disease risk at immediate lags, and weaker correlation at delayed lags, whereas O3 showed slightly negative correlation at the immediate lag (lag0) and PM2.5 did not show strong correlation (SO2: 1.04 [95% confidence interval: 1.01, 1.06]; NO2: 1.08 [1.06, 1.11]; CO: 1.04 [1.02, 1.06]; O3: 0.96 [0.93, 0.99]: statistically significant ORs at lag0 are listed). These positive and negative associations between Meniere's disease and each air pollutant were generally stronger in the age of 40-64, female, summer (June-August) season, and urban subgroups. Our results showed that hospital visits for Meniere's disease were associated with the measured concentrations of ambient air pollutants SO2, NO2, CO, and PM10. Further studies are required to confirm these associations and find their mechanisms.

Hold the Salt: History of Salt Restriction as a First-line Therapy for Menière's Disease

OBJECTIVES

To determine the historical origins of the usage of the salt restriction diet as an intervention for Menière's disease (MD).

METHODS

Articles on MD and salt restriction were identified using Pubmed and Google scholar. Original manuscripts from 19th and 20th century as well as selected otological textbooks in English, German, and French were also reviewed.

RESULTS

The oldest recommendation of salt restriction in the literature was by Dederding (1889-1955) in 1929. She and her mentor, Sydney Holger Mygind (1884-1970), believed MD was caused by dysfunctional water metabolism. In several published manuscripts, they proposed that a reduced salt and fluid diet was an effective treatment for MD. Their contemporaries supported their findings, most notably, Albert C. Furstenberg (1890-1969) who suggested salt restriction alone as treatment for MD. Furstenberg, in his initial study implementing salt restriction in 15 patients with MD and then in a larger study with 150 patients, was the first to produce results that supported salt restriction as therapy for MD. It was not until 1980, when LB Jongkees first published his criticism of this treatment, that salt restriction was questioned. Since then, numerous published articles have been critical of salt restriction therapy and skeptical of its initial adoption into clinical practice.

CONCLUSIONS

Since Dederding's and Mygind's publications in 1929 and Furstenberg's trial in 1934, the salt restriction diet has remained a primary first-line treatment for MD. Since the 1950s, various publications have both supported and argued this treatment, and the evidence of its validity remains inconclusive.

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.

A hypothetical proposal for association between migraine and Meniere's disease

Meniere's disease (MD) is a chronic condition affecting the inner ear whose precise etiology is currently unknown. We propose the hypothesis that MD is a migraine-related phenomenon which may have implications for future treatment options for both diseases. The association between MD and migraine is both an epidemiological and a mechanistic one, with up to 51% of individuals with MD experiencing migraine compared to 12% in the general population. The presence of endolymphatic hydrops in those with MD may be the factor that unites the two conditions, as hydropic inner ears have an impaired ability to maintain homeostasis. Migraine headaches are theorized to cause aura and symptoms via spreading cortical depression that ultimately results in substance P release, alterations in blood flow, and neurogenic inflammation. Chronically hydropic inner ears are less able to auto-regulate against the changes induced by active migraine attacks and may ultimately manifest as MD. This same vulnerability to derangements in homeostasis may also explain the common triggering factors of both MD attacks and migraine headaches, including stress, weather, and diet. Similarly, it may explain the efficacy of common treatments for both diseases: current migraine treatments such as anti-hypertensives and anti-convulsants have shown promise in managing MD. Though the etiology of both MD and migraine is likely multifactorial, further exploration of the association between the two conditions may illuminate how to best manage them in the future. MD is likely a manifestation of cochleovestibular migraine, which occurs as a result of migraine related changes in both the cochlea and vestibule.

Intratympanic therapy in Meniere's syndrome or disease: up to date evidence for clinical practice

BACKGROUND

Meniere's syndrome or disease (MS/D) is typically characterised by episodic vertigo, aural fullness, tinnitus and fluctuating hearing loss. There are multiple options available for treatment with variation in consensus on the best intervention.

OBJECTIVE

To evaluate the evidence on the efficacy of intratympanic therapies [steroids, gentamicin, antivirals and other therapies] on the frequency and severity of vertigo and other symptoms of MS/D.

SEARCH STRATEGY

A literature search was performed on AMED, EMBASE, HMIC, MEDLINE, PsycINFO, BNI, CINAHL, HEALTH BUSINESS ELITE, CENTRAL and Cochrane Ear, Nose and Throat disorders group trials register using various MeSH. The search was restricted to English and human subjects, and the last date of search was December 2014.

SELECTION CRITERIA

Randomised controlled trials of intratympanic therapies [steroids, gentamicin antivirals and latanoprost] versus a placebo or another treatment.

RESULTS

We analysed 8 RCT's comparing intratympanic steroids, gentamicin, ganciclovir (antiviral) and latanoprost versus another form of intratympanic treatment or placebo.

CONCLUSIONS

On the basis of 6 RCT's (n = 242), there is evidence to support the effectiveness of intratympanic steroids and gentamicin to control symptoms of vertigo in MS/D albeit with a risk of hearing loss with gentamicin. However, there was no consensus found on doses or treatment protocols. There was no evidence to support the use of other forms of intratympanic therapy (antivirals and latanoprost) in MS/D.

Viral causes of hearing loss: a review for hearing health professionals

A number of viral infections can cause hearing loss. Hearing loss induced by these viruses can be congenital or acquired, unilateral or bilateral. Certain viral infections can directly damage inner ear structures, others can induce inflammatory responses which then cause this damage, and still others can increase susceptibility or bacterial or fungal infection, leading to hearing loss. Typically, virus-induced hearing loss is sensorineural, although conductive and mixed hearing losses can be seen following infection with certain viruses. Occasionally, recovery of hearing after these infections can occur spontaneously. Most importantly, some of these viral infections can be prevented or treated. For many of these viruses, guidelines for their treatment or prevention have recently been revised. In this review, we outline many of the viruses that cause hearing loss, their epidemiology, course, prevention, and treatment.

The prevalence and identity of Chlamydia-specific IgE in children with asthma and other chronic respiratory symptoms

Background

Recent studies have confirmed the presence of viable Chlamydia in the bronchoalveolar lavage (BAL) fluid of pediatric patients with airway hyperresponsiveness. While specific IgG and IgM responses to C. pneumoniae are well described, the response and potential contribution of Ag-specific IgE are not known. The current study sought to determine if infection with Chlamydia triggers the production of pathogen-specific IgE in children with chronic respiratory diseases which might contribute to inflammation and pathology.

Methods

We obtained BAL fluid and serum from pediatric respiratory disease patients who were generally unresponsive to corticosteroid treatment as well as sera from age-matched control patients who saw their doctor for wellness checkups. Chlamydia-specific IgE was isolated from BAL and serum samples and their specificity determined by Western blot techniques. The presence of Chlamydia was confirmed by species-specific PCR and BAL culture assays.

Results

Chlamydial DNA was detected in the BAL fluid of 134/197 (68%) patients. Total IgE increased with age until 15 years old and then decreased. Chlamydia-specific IgE was detected in the serum and/or BAL of 107/197 (54%) patients suffering from chronic respiratory disease, but in none of the 35 healthy control sera (p < 0.0001). Of the 74 BAL culture-positive patients, 68 (91.9%, p = 0.0001) tested positive for Chlamydia-specific IgE. Asthmatic patients had significantly higher IgE levels compared to non-asthmatics (p = 0.0001). Patients who were positive for Chlamydia DNA or culture had significantly higher levels of serum IgE compared to negative patients (p = 0.0071 and p = 0.0001 respectively). Only 6 chlamydial antigens induced Chlamydia-specific IgE and patients with C. pneumoniae-specific IgE had significantly greater levels of total IgE compared to C. pneumoniae-specific IgE negative ones (p = 0.0001).

Conclusions

IgE antibodies play a central role in allergic inflammation; therefore production of Chlamydia-specific IgE may prove significant in the exacerbation of chronic, allergic airway diseases, thus highlighting a direct role for Chlamydia in asthma pathogenesis.

Alzheimer's Disease: APP, Gamma Secretase, APOE, CLU, CR1, PICALM, ABCA7, BIN1, CD2AP, CD33, EPHA1, and MS4A2, and Their Relationships with Herpes Simplex, C. Pneumoniae, Other Suspect Pathogens, and the Immune System

Alzheimer's disease susceptibility genes, APP and gamma-secretase, are involved in the herpes simplex life cycle, and that of other suspect pathogens (C. pneumoniae, H. pylori, C. neoformans, B. burgdorferri, P. gingivalis) or immune defence. Such pathogens promote beta-amyloid deposition and tau phosphorylation and may thus be causative agents, whose effects are conditioned by genes. The antimicrobial effects of beta-amyloid, the localisation of APP/gamma-secretase in immunocompetent dendritic cells, and gamma secretase cleavage of numerous pathogen receptors suggest that this network is concerned with pathogen disposal, effects which may be abrogated by the presence of beta-amyloid autoantibodies in the elderly. These autoantibodies, as well as those to nerve growth factor and tau, also observed in Alzheimer's disease, may well be antibodies to pathogens, due to homology between human autoantigens and pathogen proteins. NGF or tau antibodies promote beta-amyloid deposition, neurofibrillary tangles, or cholinergic neuronal loss, and, with other autoantibodies, such as anti-ATPase, are potential agents of destruction, whose formation is dictated by sequence homology between pathogen and human proteins, and thus by pathogen strain and human genes. Pathogen elimination in the ageing population and removal of culpable autoantibodies might reduce the incidence and offer hope for a cure in this affliction.

Intratympanic gentamicin injections for the treatment of Ménière's disease

Objective

To assess the success rate and complications of treatment with injections of intratympanic gentamicin to the middle ear of patients with Ménière's disease.

Study Design

Case series with chart review.

Setting

A tertiary otologic private ENT clinic.

Subjects and Methods

Patients with Ménière's disease, who had not responded to medical treatment. Included in the sample were patients with Ménière's disease who had been treated with injections of gentamicin into the middle ear. After each gentamicin application, patients were monitored for their symptoms and hearing. If symptoms persisted, they received another intratympanic injection of gentamicin. This method is referred to as the variable titration method. A retrospective chart review was performed, and questionnaires were used to assess hearing, functional status, tinnitus, ear fullness sensation, and the control of vertigo attacks in response to treatment.

Results

Nineteen patients were sampled. Eighteen patients (94%) had complete or substantial control of vertigo. Five patients (26%) had worse hearing results on their post-treatment audiogram, averaging 13 dB hearing loss (range, 5-25 dB). In response to the questionnaires, all patients reported a significant improvement in the quality of life after treatment.

Conclusion

The treatment was found to be highly effective. The variable titration method of injection prevents unnecessary injections for patients whose symptoms have already subsided.

Virus-specific IgE enhances airway responsiveness on reinfection with respiratory syncytial virus in newborn mice

BACKGROUND

Respiratory syncytial virus (RSV)-specific IgE is a component of the host response to RSV infection, but its role in the subsequent enhancement of altered airway responsiveness is unknown.

OBJECTIVE

To define the role of RSV-specific IgE in the enhancement of airway responsiveness on reinfection of newborn mice.

METHODS

Mice were infected as newborns with RSV and were reinfected 5 weeks later. The role of IgE was determined by documenting RSV-specific IgE response after neonatal infection, and by assessing airway responsiveness on reinfection.

RESULTS

After neonatal infection, wild-type (WT) mice developed an RSV-specific IgE response. On reinfection, these mice developed enhanced airway hyperresponsiveness (AHR), airway eosinophilia, and mucus hyperproduction, and their T-cell cytokine response was skewed toward a T(H)2 phenotype. None of these altered responses developed on reinfection of IL-4(-/-)/IL-13(-/-) mice, and no RSV-specific IgE could be detected after neonatal infection of these mice. Fc epsilon RI(-/-) mice did not develop the enhanced AHR on reinfection, and airway eosinophilia and mucus production were significantly attenuated. These responses could be restored in deficient mice reconstituted with WT mast cells. In RSV-infected newborn WT mice, administration of anti-IgE prevented the enhancement of AHR and attenuated eosinophilia and mucus hyperproduction on reinfection, an effect that was associated with diminished T(H)2 cytokine production and increased IFN-gamma production.

CONCLUSION

Respiratory syncytial virus-specific IgE enhances the development of T(H)2-biased airway responsiveness on reinfection of mice initially infected as newborns.

Induction of high-affinity IgE receptor on lung dendritic cells during viral infection leads to mucous cell metaplasia

Respiratory viral infections are associated with an increased risk of asthma, but how acute Th1 antiviral immune responses lead to chronic inflammatory Th2 disease remains undefined. We define a novel pathway that links transient viral infection to chronic lung disease with dendritic cell (DC) expression of the high-affinity IgE receptor (FcepsilonRIalpha). In a mouse model of virus-induced chronic lung disease, in which Sendai virus triggered a switch to persistent mucous cell metaplasia and airway hyperreactivity after clearance of replicating virus, we found that FceRIa(-/-) mice no longer developed mucous cell metaplasia. Viral infection induced IgE-independent, type I IFN receptor-dependent expression of FcepsilonRIalpha on mouse lung DCs. Cross-linking DC FcepsilonRIalpha resulted in the production of the T cell chemoattractant CCL28. FceRIa(-/-) mice had decreased CCL28 and recruitment of IL-13-producing CD4(+) T cells to the lung after viral infection. Transfer of wild-type DCs to FceRIa(-/-) mice restored these events, whereas blockade of CCL28 inhibited mucous cell metaplasia. Therefore, lung DC expression of FcepsilonRIalpha is part of the antiviral response that recruits CD4(+) T cells and drives mucous cell metaplasia, thus linking antiviral responses to allergic/asthmatic Th2 responses.

Randomized double-blinded, placebo-controlled clinical trial of famciclovir for reduction of Ménière's disease symptoms

OBJECTIVE

To conduct a clinical trial of famciclovir for symptom control in Meniere's disease.

STUDY DESIGN AND SETTING

Randomized, double-blinded placebo-controlled clinical trial in a tertiary referral center, with 12 subjects in the active treatment arm and 11 subjects in the placebo arm.

RESULTS

There were no serious adverse events. Twenty-five percent of the famciclovir group and 18% of the placebo group showed a reduction in number of vertigo spells, the primary efficacy endpoint. This difference was not statistically significant. All subjects improved in dizziness and health-related quality of life. There was a trend for the famciclovir arm to have less fluctuation in hearing relative to the placebo arm.

CONCLUSION

No dramatic effects of famciclovir were found on vertigo or dizziness. Some promising effects on reduction of the fluctuation in hearing were observed.

SIGNIFICANCE

Famciclovir may suppress the fluctuation of hearing in Meniere's disease, but had a minimal effect on vertigo or dizziness symptoms in this study. The probable multifactorial etiology in Meniere's disease requires that further studies be conducted to determine the effects of antiviral medications.

EBM RATING

A.

The role of virus-specific immunoglobulin E in airway hyperresponsiveness

Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis during infancy and is associated with subsequent wheezing and asthma, but the nature of this association is not fully understood. We investigated the role of RSV-specific IgE antibodies in the pathophysiology of virus-induced airway dysfunction in a mouse model. Lung infection with RSV resulted in significant increases in mRNA expression for IgE and both of its high- and low-affinity receptors. In serum, virus-specific IgE antibodies reached peak levels by Day 21 after infection. Data from in vitro experiments show that RSV can induce mast cell degranulation, but only if these cells are sensitized with specific IgE. When passively sensitized in vivo with virus-specific IgE, mice developed exaggerated airway responsiveness to methacholine on airway infection, an effect that required the high-affinity receptor of IgE. These data suggest that RSV-specific IgE may contribute to the pathophysiology of airway dysfunction in children who develop this class of specific antibody.

Incidence of virus infection as a cause of Meniere?s disease or endolymphatic hydrops assessed by electrocochleography

Meniere's disease (MD) may follow viral infection such as by neurotropic viruses known to invade the endolymphatic sac (ES) and provoke endolymphatic hydrops (EH). The objective of this study was to investigate whether neurotropic viruses may cause infection of the inner ear and provoke EH. Antiviral immunoglobulin (IgG) assay against herpes simplex 1 (HSV1), herpes simplex 2 (HSV2), adenovirus (ADV), varicella zoster virus (VZV) and cytomegalovirus (CMV) were performed in 109 patients with an advanced stage of MD and compared with those obtained from 26 patients operated on because of vestibular schwannoma (VS), who served as a control group, to evaluate whether there is an association between the IgG levels and the ECoGs summating potential/action potential ratio (SP/AP ratio) in the MD group. In MD patients, the IgG titre against VZV and ADV were significantly higher than in the control (schwannoma) group. However, no correlation was found between the IgG levels against ADV and VZV with the SP/AP ratio. Neurotropic viruses such VZV and ADV may play a role in the pathogenesis of MD, despite the absence of association between the levels of IgG titres and the SP/AP ratio.

Herpes simplex virus and Meniere's disease

OBJECTIVE/HYPOTHESIS

This study was designed to investigate the hypothesis that Meniere's disease is associated with herpes simplex virus (HSV) reactivation in the vestibular ganglion.

STUDY DESIGN

Case control study.

METHODS

Vestibular ganglia were obtained from archival surgical pathology specimens from patients undergoing vestibular neurectomy for vertigo caused by Meniere's disease. All patients met criteria for classification as definite Meniere's disease according to American Academy of Otolaryngology/Head and Neck Surgery (AAO-HNS) criteria. Control specimens were obtained from willed body donors. Sections from each ganglion were studied for prevalence of viral DNA using a nested polymerase chain reaction designed to amplify the HSV DNA polymerase gene. Quantitative analysis determined the number of viral copies per standard unit of ganglionic DNA.

RESULTS

HSV DNA was more prevalent in paraffin embedded ganglia from patients with Meniere's disease (100%) than in fresh-frozen control ganglia (81%) (P =.02). Fixation and paraffin embedding substantially reduced recovery of HSV virus in selected control specimens. Quantitative analysis found no correlation between viral copy number in control ganglia processed frozen versus formalin fixed and paraffin embedded.

CONCLUSIONS

HSV is more commonly isolated from vestibular ganglia of patients with Meniere's disease than the general population. The routine histologic preparation of formalin fixation and paraffin embedding significantly altered the quantity of virus detected though not in a predictable manner. The study provides supportive evidence for a viral etiology in Meniere's disease.

[Immuno-pathogenesis in Meniere's disease]

Since the report of Duke in which an allergic etiology was considered to be the cause of Meniere's disease, the hypothesis that a certain type of Meniere's disease is generated through immuno-pathological mechanisms has been advocated for 70 years. During this period, another entity of immune-mediated inner ear disorders, i. e., autoimmune inner ear disease was introduced. Fundamental immunological phenomena of the inner ear have been rapidly elucidated since 1980. The endolymphatic sac is the only site which contains immuno-competent cells within the inner ear. The inner ear is capable of mounting active immune responses when appropriately stimulated and the endolymphatic sac plays an integral function for inner ear immune response. Actually, many reports have been published that link immunity and Meniere's disease with a variety of proposed immune-related etiologies from autoimmunity to non-autoimmunity. It is suggested that immune injury to the endolymphatic sac plays an important role in the pathogenesis of Meniere's disease. These functional and morphological circumstances strongly suggest that an immunological etiology of Meniere's disease is not theoretically unfounded.

The three faces of vestibular ganglionitis

We present temporal bone and clinical evidence that common syndromes of recurrent vertigo are caused by a viral infection of the vestibular ganglion. In the present series, histopathologic and radiologic changes in the vestibular ganglion and meatal ganglion were consistent with a viral inflammation of ganglion cells in cases of Meniere's disease, benign paroxysmal positional vertigo, and vestibular neuronitis. Clinical observations of multiple neuropathies involving cranial nerves V, VII, and VIII on the same side in patients with recurrent vertigo are best explained by a cranial polyganglionitis caused by a neurotrophic virus, which is reactivated by a stressful event later in life. The reactivation of the latent virus may manifest as one of the above vertigo syndromes, depending on the part of the vestibular ganglion that is inflamed, the type and strain of the virus, and host resistance.

Menière's disease as a manifestation of vestibular ganglionitis

OBJECTIVE

To present morphologic evidence of viral-induced vestibular nerve pathology in Menière's Disease (MD). MATERIAL STUDIED: Twelve temporal bones (TB) from 8 patients with the clinical symptoms of MD.

RESULTS

There was endolymphatic hydrops (EH) and perilymphatic fibrosis in 10 of the 12 TB from MD patients. Of the 10 TB with EH of the pars inferior, 3 also contained outpouchings in the pars superior (utricle and canals), and 3 showed apical spiral ganglion cell loss. Focal vestibular nerve axonal degeneration was observed in all but one TB.

CONCLUSION

Morphologic changes in TB of patients with MD, and clinical observations in patients with recurrent vestibulopathy, support the concept that the pathologic mechanism responsible for auditory and vestibular symptoms in MD may be reactivation of a latent viral vestibular ganglionitis.

Persistent Measles Virus Infection as a Possible Cause of Otosclerosis: State of the Art

The etiopathogenesis of otosclerosis is still largely unexplained and remains controversial. Morphologic examinations have shown the presence of a chronic inflammation in otosclerotic tissue. Among the proposed explanations for this inflammation are an immunologic reaction against collagen, mutations of collagen gene 1A1, and a viral infection.

In this paper, we focus on the role of measles virus in otosclerosis, and we review the current literature, devoting particular attention to a suspected paramyxoviral etiopathogenesis in Paget's disease. Our examination of footplate fragments by reverse transcription polymerase chain reaction testing in 95 patients with otosclerosis revealed the presence of measles virus RNA in 83% of cases. Quantification of measles virus immunoglobulin G (IgG) in otosclerosis patients indicated that the ratio of antimeasles virus IgG in total IgG was higher in perilymph than in serum. Furthermore, an almost identical incidence of otosclerosis and measles virus-caused mortality in women suggests that women are more susceptible to measles virus infection. Finally, since the introduction of the measles virus vaccination program in Europe, there has been a decline in the incidence of otosclerosis. Moreover, the average age of patients at diagnosis and surgery at our hospital has increased to 54 years.

Our findings, when they are considered along with findings regarding the presence of paramyxoviral RNA in Paget's disease, support the hypothesis that measles virus is involved in the etiopathogenesis of otosclerosis.

The pathology of facial and vestibular neuronitis

OBJECTIVE

To measure disease of idiopathic nature in the ganglia of the human facial (FN) and vestibular nerves (VN).

METHOD

One hundred horizontally sectioned human temporal bones (TB) were examined under light microscopy. The TB were sectioned at 20 microm, and every 10th section was stained with hematoxylin and eosin and mounted. The volume fractions (VF) of degenerated cells in the FN ganglion and focal axonal degeneration in the VN were measured with stereologic techniques.

RESULTS

Twenty-five TB were excluded because of artifact or poor staining of the FN and VN. Fifty-one TB contained degenerated cells in the FN meatal ganglion (MG) and/or focal axonal degeneration in the VN. Thirty-one FN had degenerated cells in the MG (VF = 1% to 55%) and none in the geniculate ganglion. In 45 TB, focal axonal degeneration was found in the VN (VF = 1% to 50%; the VF was less than 15% in all but one TB). MG and VN degeneration occurred together in 25 TB. None of the cases had a history of FN paralysis, but 20 had a history of vertigo. Twenty-four TB from patients of similar ages with similar otopathologies did not reveal degeneration in the FN or VN.

CONCLUSION

The FN and VN lesions in these 51 TB may be virus-induced and reflect a higher incidence of idiopathic FN and VN neuronitis than previously thought.