Vestibular neuronitis--serum and CSF virus antibody titer

Developing a Diagnostic Algorithm for Identifying Vestibular Neuronitis in Acute Dizziness: An Overview of Epidemiology, Pathogenesis, and Evidence-Based Guidelines for Diagnostic Approaches

Vestibular neuronitis (VN) is a prevalent peripheral vestibular disorder presenting with sudden unilateral vestibular loss, leading to acute vertigo without associated cochlear or neurological symptoms. Diagnosis remains challenging due to symptom overlap with other vestibular and central disorders. This study reviews the epidemiology, pathogenesis, and diagnostic approaches for VN to propose a streamlined, evidence-based diagnostic algorithm. A comprehensive literature review was conducted, analyzing 114 studies, including randomized controlled trials, systematic reviews, and clinical guidelines. Emphasis is placed on the clinical history and bedside examinations, supported by ancillary tests to confirm the diagnosis and differentiate VN from central and other peripheral causes of vertigo. The proposed algorithm aims to enhance diagnostic precision and support clinical decision-making.

[Demographic and epidemiological risk factors in patients with acute vestibular neuritis]

OBJECTIVE

Vestibular neuritis (VN) is one of the most common peripheral vestibular balance disorder. Demographic and other risk factors associated with VN are insufficiently published. Therefore, the aim of this study is to identify associated risk factors in patients with acute VN.

METHODS

This study evaluated all hospitalized VN cases between 2017-2019. Inclusion criteria was an otoneurologically confirmed diagnosis of acute VN. Patient data was compared with data of the German normal population (Robert Koch Institute, "Gesundheit in Deutschland aktuell").

RESULTS

168 patients (Ø 59.8 years) were included. Compared with the normal German population, the study population was significantly more likely to have preexisting cardiovascular diseases, and the male patients were significantly more likely to have arterial hypertension. No significant differences were measurable between the study population and the normal population for other secondary diseases. Leukocytosis was present in 23% on admission, and 9% of patients reported a history of VZV or HSV-1 disease.

DISCUSSION

Etiology and pathogenesis of VN are poorly understood. Inflammatory and vascular causes are discussed. In this study, patients had increased prevalence of cardiovascular disease compared with the normal population, but the study population had a higher average age. Currently, it is unclear what significance nonspecific elevated leukocyte values could have as a possible sign of VN triggered by an infection. Since the number of inpatient cases with VN is rising, prospective studies should be performed to get a better understanding of the pathogenesis of the disease.

Suppression of inner ear signal intensity on fluid-attenuated inversion recovery magnetic resonance imaging in cats with vestibular disease

OBJECTIVES

Otitis media/interna (OMI) is the most common cause of peripheral vestibular disease in cats. The inner ear contains endolymph and perilymph, with perilymph being very similar in composition to cerebrospinal fluid (CSF). As a very-low-protein fluid, it would be expected that normal perilymph should suppress on fluid-attenuated inversion recovery (FLAIR) MRI sequences. Based on this, we hypothesized that MRI FLAIR sequences should provide a non-invasive way of diagnosing inflammatory/infectious diseases such as OMI in cats, something that has previously been demonstrated in humans and, more recently, in dogs.

METHODS

This was a retrospective cohort study in which 41 cats met the inclusion criteria. They were placed into one of four groups, based on presenting complaint: clinical OMI (group A); inflammatory central nervous system (CNS) disease (group B); non-inflammatory structural disease (group C); and normal brain MRI (control group; group D). Transverse T2-weighted and FLAIR MRI sequences at the level of the inner ears bilaterally were compared in each group. The inner ear was selected as a region of interest using Horos, with a FLAIR suppression ratio calculated to account for variability in signal intensity between MRIs. This FLAIR suppression ratio was then compared between groups. Statistical analyses were performed by an experienced statistician, with a general linear model used to compare mean FLAIR suppression ratio, CSF nucleated cell count and CSF protein concentration between groups.

RESULTS

The OMI group (group A) had significantly lower FLAIR suppression scores compared with all other groups. The CSF cell count was also significantly increased in the OMI (group A) and inflammatory CNS disease (group B) groups compared with the control group (group D).

CONCLUSIONS AND RELEVANCE

This study demonstrates the utility of MRI FLAIR sequences in diagnosing presumptive OMI in cats, similarly to in humans and dogs. This study is relevant to practicing veterinary neurologists and radiologists in interpreting MRI findings in cats with suspected OMI.

Study of the Comorbidity Between Cases of Acute Peripheral Vestibulopathies and COVID-19

IMPORTANCE

An infective etiology of acute peripheral vestibulopathy (APV) has long been hypothesized. In the context of coronavirus disease 2019 (COVID-19), we examined the possible comorbidity between these two entities.

OBJECTIVES

APV is the second most common cause of vestibular disorders and results from a sudden and unilateral loss of vestibular inputs. The characteristic signs and symptoms include sudden and prolonged vertigo, absence of auditory symptoms, and absence of other neurological symptoms. An infective etiology of APV has long been hypothesized on the basis of its association with respiratory tract infections and its frequent occurrence in epidemics. Possible comorbidity with herpes simplex virus type 1 reactivation or influenza virus infection has also been proposed. This study was designed to assess the possible comorbidity between APV and COVID-19.

DESIGN/SETTING/PARTICIPANTS

Quantification of the number of hospital admissions for APV over the period from February to May 2020 was carried out in 5 French hospitals. A comparison with 2018 and 2019 entries over the same period was made. Comorbidity between APV and COVID-19 infection was investigated.

RESULTS

No significant increase in admission for APV was noticed over the examination period. No significant difference was noticed among hospitals located in COVID-19 high- and low-risk zones for SARS-CoV-2. No significant increase in the severity of the APV cases was noticed. No case of comorbidity between APV and SARS-CoV-2 infection was reported. Based on our observations, no correlation was made between APV and COVID-19.

CONCLUSION

Based on our observations, COVID-19 is not statistically correlated with APV.

Change in and long-term investigation of neuro-otologic disorders in disaster-stricken Fukushima prefecture: retrospective cohort study before and after the Great East Japan Earthquake

On March 11, 2011, Japan's northeast Pacific coast was hit by a gigantic earthquake and subsequent tsunami. Soma City in Fukushima Prefecture is situated approximately 44 km north of Fukushima Daiichi Nuclear Power Plant. Soma General Hospital is the only hospital in Soma City that provides full-time otolaryngological medical care. We investigated the changes in new patients from one year before to three years after the disaster. We investigated 18,167 new patients treated at our department during the four years from April 1, 2010 to March 31, 2014. Of the new patients, we categorized the diagnoses into Meniere's disease, acute low-tone sensorineural hearing loss, vertigo, sudden deafness, tinnitus, and facial palsy as neuro-otologic symptoms. We also investigated the changes in the numbers of patients whom we examined at that time concerning other otolaryngological disorders, including epistaxis, infectious diseases of the laryngopharynx, and allergic rhinitis. The total number of new patients did not change remarkably on a year-to-year basis. Conversely, cases of vertigo, Meniere's disease, and acute low-tone sensorineural hearing loss increased in number immediately after the disaster, reaching a plateau in the second year and slightly decreasing in the third year. Specifically, 4.8% of patients suffering from these neuro-otologic diseases had complications from depression and other mental diseases. With regard to new patients in our department, there was no apparent increase in the number of patients suffering from diseases other than neuro-otologic diseases, including epistaxis, and allergic rhinitis. Patients suffering from vertigo and/or dizziness increased during the first few years after the disaster. These results are attributed to the continuing stress and tension of the inhabitants. This investigation of those living in the disaster area highlights the need for long-term support.

Is vestibular neuritis an immune related vestibular neuropathy inducing vertigo?

OBJECTIVES

To review the current knowledge of the aetiology of vestibular neuritis including viral infections, vascular occlusion, and immunomediated mechanisms and to discuss the pathogenesis with relevance to pharmacotherapy.

SYSTEMATIC REVIEW METHODOLOGY

Relevant publications on the aetiology and treatment of vestibular neuritis from 1909 to 2013 were analysed.

RESULTS AND CONCLUSIONS

Vestibular neuritis is the second most common cause of peripheral vestibular vertigo and is due to a sudden unilateral loss of vestibular function. Vestibular neuronitis is a disorder thought to represent the vestibular-nerve equivalent of sudden sensorineural hearing loss. Histopathological studies of patients who died from unrelated clinical problems have demonstrated degeneration of the superior vestibular nerve. The characteristic signs and symptoms include sudden and prolonged vertigo, the absence of auditory symptoms, and the absence of other neurological symptoms. The aetiology and pathogenesis of the condition remain unknown. Proposed theories of causation include viral infections, vascular occlusion, and immunomediated mechanisms. The management of vestibular neuritis involves symptomatic treatment with antivertiginous drugs, causal treatment with corticosteroids, and physical therapy. Antiviral agents did not improve the outcomes.

Zapalenie nerwu przedsionkowego (vestibular neuritis) – opis przypadku

Vestibular neuritis is a group of symptoms resulting from a sudden unilateral vestibular dysfunction. It seldom occurs in children (approximately 7%). Its etiology and pathogenesis are unknown, although most researchers consider viral infection to be a causative factor. The clinical symptoms appear rapidly, exacerbate within a few hours and include vertigos, accompanied by nausea, vomiting and paralytic nystagmus, which intensifies with head movements. This is a case of a 15-year-old boy, so far healthy and with normal psychomotor development, who was admitted to the hospital ward due to exacerbating vertigos accompanied by nausea and balance disorders.

Physiopathology of peripheral non-Menière's vestibular disorders

This paper reviews the physiopathological basis of some labyrinthine or vestibular nerve disorders illustrating a particular mode of vestibular dysfunction. The discovery of the physiopathology of these disorders has relied on neuroanatomical data, histopathological observations of human temporal bones, historical principles of vestibular physiology, surgical exploration, blood testing which provides indirect evidence of immune or metabolic disorders, and results from animal experiments. While all data are valid, advances in sensory cell physiology, development of new vestibular tests, and progress in imaging techniques are necessary in order for a better understanding of the mechanisms involved in vestibular end organ dysfunction to be obtained.

Vestibular neuritis: an overview using a classical case

Although acute unilateral and/or bilateral vestibular paralysis, known as vestibular neuronitis, is the second most common cause of vertigo (the most common is benign paroxysmal positional vertigo (BPPV), it is fraught with controversies. The clinical symptoms and methods of treatment of vestibular neuronitis are well defined; however, the etiology and pathophysiology of this disorder are still sketchy. Furthermore, there are no specific diagnostic tests available, and unfortunately, there are no animal models for this disorder. The purpose of this paper is to present an overview of those controversies using a classical case of vestibular neuronitis.

Detection of HSV-I nucleic acids in rat vestibular ganglia

Rats were infected with HSV-I through the middle ear. DNA and RNA were extracted from the vestibular ganglia, trigeminal ganglia, cerebrum, cerebellum and brainstem in the productive or latent state after inoculation. DNA and RNA were applied for polymerase chain reaction (PCR) to detect HSV-I genomes. In particular, in the RNA PCR, the latent-associated transcript (LAT) mRNA, which is said to be present in the cervical or trigeminal ganglia at much lower levels during the productive state, was detected. In the productive state, DNA was clearly detected in all samples whereas LAT was detected only in the trigeminal ganglion on the inoculated side, cerebrum and cerebellum. In the latent state, DNA was detected in the vestibular ganglion only on the inoculated side, bilateral trigeminal ganglia, cerebrum, cerebellum and brainstem; LAT was detected in the vestibular ganglion on the inoculated side, the bilateral trigeminal ganglia and brainstem. These data indicate that HSV-I can establish latent infection in the vestibular ganglia in a similar way as in the cervical or trigeminai ganglia.

Vestibular neuronitis in aged patients: results from an epidemiological survey by questionnaire in Japan

An epidemiological survey of vestibular neuronitis in Japan was done using a questionnaire. Answer sheets were obtained from 619 patients with vestibular neuronitis. In order to evaluate data from aged patients, 74 cases were singled out. The following results were obtained: i) There was no sexual difference and no laterality of affected side; ii) There was no case of bilateral vestibular neuronitis; iii) Ten cases were reported as recurrent. Aged patients had a relatively high rate of recurrence; iv) About 10% of 74 cases had had an upper respiratory tract infection, and this rate was lower than that for patients under 65 years of age; v) Thirty-five cases had complications. Hypertension was the most common complication; vi) The caloric test was re-used in 28 cases. The continued existence of caloric CP was observed in 23 cases upon re-examination.

The aetiology of dizziness and how to examine a dizzy patient

Dizziness embraces various sensations of spatial disorientation. A common symptom, it has been experienced by at least one third of the population by the age of 65. Peripheral causes include disorders of the labyrinth and vestibular nerve such as Ménière's disease, benign paroxysmal positional vertigo, acute vestibulopathy (vestibular neuronitis) and acoustic neuroma. The most common lesions of the central nervous system that cause dizziness are infratentorial ischaemia, mechanical trauma, multiple sclerosis and cerebellar atrophy. Other aetiological factors include intoxications, psychogenic causes, cervical problems and cardiovascular diseases. The history and physical examination are the cornerstones of the search for the cause of dizziness. The most valuable otological methods are electronystagmography and audiometry. Of the clinical neurophysiological methods, brainstem auditory evoked potentials are more useful than electroencephalography. Computed tomography and magnetic resonance imaging should be used when a CNS disorder is suspected.

Latent HSV-I infection in rat vestibular ganglia

The vestibular ganglia of rats having no clinical symptoms after inoculation of HSV-I were examined by Polymerase Chain Reaction (PCR) in order to prove latent HSV-I infection. The rats were divided into two groups: one inoculated with HSV-I into the middle ear cavity (m.i. group), and the other into the peritoneal space (i.p. group). In the m.i. group, 67% of the vestibular ganglia on the inoculated side and 0% on the opposite side were positive. In the i.p. group, 60% of the vestibular ganglia on both sides were positive. These data indicate that HSV-I can establish latent infection in the vestibular ganglia. Furthermore, we assumed that reactivation of HSV-I genomes in the vestibular ganglia might lead to disorders of the vestibular system.

Chronic herpes simplex virus and varicella zoster virus infection

After defining such terms as persistent and chronic infection, latency, recurrence, recrudescence, and exogenous reinfection they are applied to infections with HSV and VZV. Possible factors determining pathogenicity are discussed, and an overview is given of the wide range of illnesses and case reports ascribed to HSV and VZV infections. Various types of infection afford different diagnostic procedures. Besides virus isolation supplemented by viral antigen identification IgG antibody tests (increase in titer) may be useful. IgG subtype and IgA antibody determinations appear to be of limited value. Despite the rather large number of available tests, there are still considerable shortcomings in their ultimate significance as to the patient's disease. Thus, some new experimental approaches are mentioned.

Vestibular neuronitis. An otoneurological evaluation

Eighty-one cases with vestibular neuronitis were examined. The diagnostic criteria were a sudden onset of vertigo without previous symptoms, spontaneous nystagmus towards the healthy side, totally extinguished caloric responses with 44 degrees C and 30 degrees C water irrigation and no involvement of hearing associated with the onset of the disease. The series was divided into a prospective and a retrospective group. The prospective group A was examined at the acute stage, about 1 month and 1 year afterwards. The retrospective group B fulfilled the same criteria as group A and was examined 1-8 years after the acute stage. The results of the acute stage in group B were analysed from the case history reports, electronystagmo- and audiograms. The preceding and predisposing factors and symptoms were inquired. The examination scheme included the clinical otoneurological examination, the nystagmographic, audiological and clinical neurophysiological measurements and the serological and hematological specimens were collected at the acute stage of group A to examine the role of virus infections in the etiology of vestibular neuronitis. The liquor specimens of 16 cases available in group A were analysed. A recent respiratory infection was reported by 9 cases (27.3 percent) in group A and by 18 cases (37.5 percent) in group B. The serological evidence (increase of IgM-antibodies) was observed in 1 case against influenza A and in 1 case against parainfluenza 3 and the hematological examinations revealed clues of virus infection in 6 cases (18.2 percent) of group A. Cell counts and protein analyses of the liquor specimens were within normal limits. Cases with arterial hypertension under medical control were observed in 15.2 percent of group A and 14.6 percent in group B. These figures do not exceed the age- and sex-correlated prevalence of arterial hypertension in Finnish population. The clinical symptoms included an acute chiefly rotatory vertigo associated with nausea and vomiting without subjective involvement of hearing. The prominent symptoms lessened gradually during the first week and most of the patients were able to their earlier work after one month. The prognosis of the disease was good. The clinical otoneurological findings of the acute stage included spontaneous nystagmus with Frenzel's glasses and disturbances of the vestibulospinal tests. These abnormalities improved markedly during the follow-up period. The results of electronystagmography were characteristic of a pure peripheral vestibular disorder. Nystagmic beats were observed almost regularly in the pendular eye-tracking test at the acute stage examination.(ABSTRACT TRUNCATED AT 400 WORDS)