Sudden Sensorineural Hearing Loss in Mild COVID-19: Case Series and Analysis of the Literature

Sudden Sensorineural Hearing Loss after COVID-19 Vaccination: A Review of the Available Evidence through the Prism of Causality Assessment

Sudden sensorineural hearing loss (SSNHL), a rare audiological condition that accounts for 1% of all cases of sensorineural hearing loss, can cause permanent hearing damage. Soon after the launch of global COVID-19 vaccination campaigns, the World Health Organization released a signal detection about SSNHL cases following administration of various COVID-19 vaccines. Post-marketing studies have been conducted in different countries using either pharmacovigilance or medico-administrative databases to investigate SSNHL as a potential adverse effect of COVID-19 vaccines. Here, we examine the advantages and limitations of each type of post-marketing study available. While pharmacoepidemiological studies highlight the potential association between drug exposure and the event, pharmacovigilance approaches enable causality assessment. The latter objective can only be achieved if an expert evaluation is provided using internationally validated diagnostic criteria. For a rare adverse event such as SSNHL, case information and quantification of hearing loss are mandatory for assessing seriousness, severity, delay onset, differential diagnoses, corrective treatment, recovery, as well as functional sequelae. Appropriate methodology should be adopted depending on whether the target objective is to assess a global or individual risk.

The First Cases of Sudden Sensorineural Hearing Loss Post Coronavirus Disease in Children

To investigate the incidence, characteristics, diagnosis, treatment, and prognosis of coronavirus disease (COVID-19)-related sudden sensorineural hearing loss (SSNHL) in children, three cases of SSNHL after COVID-19 infection in children were analyzed. ENT clinical examination of all cases was normal. Only the third child had a first degree left-beating optokinetic nystagmus, compatible with right peripheral vestibulopathy. The audiogram indicated unilateral severe SSNHL in all frequencies. Computed tomography and magnetic resonance imaging of the brain and temporal bones also showed absence of pathology of the related structures. Oral methylprednisolone was administered to the first two cases, whereas intravenous methylprednisolone in a tapering form was administered to the third case. Additionally, the children underwent intratympanic dexamethasone injections and hyperbaric oxygen therapy with hearing improvement in lower and middle frequencies. The prognosis of COVID-19-related SSNHL in children is closely related to the onset of treatment. The combination of glucocorticoids, intratympanic dexamethasone injections, and hyperbaric oxygen therapy could be effective for COVID- 19-related SSNHL in children. Further large-scale, multicenter studies should be conducted to investigate the pathophysiology, diagnosis, treatment, and prognosis of COVID- 19-related SSNHL.

A review on the impacts of COVID-19 on the auditory system: Implications for public health promotion research

Background

Currently, there are few studies on the relationship between COVID-19 and the auditory system. In the current study, a review of the studies conducted in the fields of etiopathology, clinical manifestations, research, and treatment of hearing loss caused byCOVID-19 was conducted, which can be used as a baseline for future studies.

Methods

We utilized the research approach suggested by Arksey and O'Malley to carry out this scoping review. Search was conducted in Farsi and English with a focus on the onset of hearing loss in patients with COVID-19 through Medline and PubMed, and Google Scholar search engine. Studies included were those involving adult patients diagnosed with COVID-19 who experienced hearing loss, ear pain, ear discharge, and otitis media. Studies were eligible for inclusion if there was a description of the otologic dysfunction, specifically onset, duration, or clinical outcomes.

Results

Among 90 studies identified, 35 studies were included in the review process. Our findings suggest several possible mechanisms for sudden sensorineural hearing loss (SSNHL) in COVID-19 patients, and COVID-19 infection could have deleterious effects on the inner ear, specifically on the hair cells of the cochlea despite patients being asymptomatic and early identification of SSNHL in COVID-19patients can save the hearing and also patient.

Conclusion

Hearing loss in COVID-19 infection has not received much attention by health care professionals. Sensorineural hearing loss (SNHL), tinnitus, and/or vertigo have been shown to occur during and following COVID-19 infection. Due to lack of research studies, and the inconsistency and even contradictory of the findings, it remains questionable whether COVID-19 contributes to the high incidence of hearing loss. The proper understanding of the mechanisms behind hearing loss in COVID-19 infections needs further research. However, it seems likely that SNHL could be included among the manifestations of those-called "long COVID" syndrome.

LINE-1 global DNA methylation, iron homeostasis genes, sex and age in sudden sensorineural hearing loss (SSNHL)

BACKGROUND

Sudden sensorineural hearing loss (SSNHL) is an abrupt loss of hearing, still idiopathic in most of cases. Several mechanisms have been proposed including genetic and epigenetic interrelationships also considering iron homeostasis genes, ferroptosis and cellular stressors such as iron excess and dysfunctional mitochondrial superoxide dismutase activity.

RESULTS

We investigated 206 SSNHL patients and 420 healthy controls for the following genetic variants in the iron pathway: SLC40A1 - 8CG (ferroportin; FPN1), HAMP - 582AG (hepcidin; HEPC), HFE C282Y and H63D (homeostatic iron regulator), TF P570S (transferrin) and SOD2 A16V in the mitochondrial superoxide dismutase-2 gene. Among patients, SLC40A1 - 8GG homozygotes were overrepresented (8.25% vs 2.62%; P = 0.0015) as well SOD2 16VV genotype (32.0% vs 24.3%; P = 0.037) accounting for increased SSNHL risk (OR = 3.34; 1.54-7.29 and OR = 1.47; 1.02-2.12, respectively). Moreover, LINE-1 methylation was inversely related (r2 = 0.042; P = 0.001) with hearing loss score assessed as pure tone average (PTA, dB HL), and the trend was maintained after SLC40A1 - 8CG and HAMP - 582AG genotype stratification (ΔSLC40A1 = + 8.99 dB HL and ΔHAMP = - 6.07 dB HL). In multivariate investigations, principal component analysis (PCA) yielded PC1 (PTA, age, LINE-1, HAMP, SLC40A1) and PC2 (sex, HFEC282Y, SOD2, HAMP) among the five generated PCs, and logistic regression analysis ascribed to PC1 an inverse association with moderate/severe/profound HL (OR = 0.60; 0.42-0.86; P = 0.0006) and with severe/profound HL (OR = 0.52; 0.35-0.76; P = 0.001).

CONCLUSION

Recognizing genetic and epigenetic biomarkers and their mutual interactions in SSNHL is of great value and can help pharmacy science to design by pharmacogenomic data classical or advanced molecules, such as epidrugs, to target new pathways for a better prognosis and treatment of SSNHL.

Efficacy and safety of Ginkgo biloba extract as an adjuvant in the treatment of Chinese patients with sudden hearing loss: a meta-analysis

CONTEXT

Ginkgo biloba Linn (Ginkgoaceae) [leaves extract (GBE)] is authorized for the treatment of sudden hearing loss (SHL); however, its clinical feasibility in SHL has not been thoroughly investigated.

OBJECTIVE

To evaluate the efficacy and safety of adjuvant GBE in the treatment of SHL.

MATERIALS AND METHODS

We used PubMed, EMBASE, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang, Chinese Scientific Journal Database, China Biomedical Database for literature research, starting from inception to 30 June 2022. The key terms: Ginkgo biloba extract, Sudden Sensorineural Deafness. This meta-analysis contained randomized controlled trials that compared the safety and efficacy of the combination of GBE and general treatments (GT) with GT alone for SHL. The extracted data were analyzed using Revman5.4 software with risk ratio (RR), 95% confidence intervals (CI) and mean difference (MD).

RESULTS

Our meta-analysis included 27 articles with a total of 2623 patients. The results revealed that the effects of GBE adjuvant therapy was superior than GT (total effective rate: RR = 1.22, 95% CI: 1.18-1.26, p < 0.00001), the pure tone hearing threshold (MD = 12.29, 95% CI: 11.74-12.85, p < 0.00001) and hemorheology indexes (whole blood high shear viscosity: MD = 1.46, 95% CI: 0.47-2.44, p = 0.004) after treatment were significantly improved compared to non-treatment, while there was no significant difference as for hematocrit (red blood cells) (MD = 4.15, 95% CI: -7.15-15.45, p = 0.47).

CONCLUSION

The efficacy of GBE + GT for the treatment of SHL may be more promising than GT alone.

Clinical utility of inflammatory biomarkers in COVID-19-related sudden sensorineural hearing loss

BACKGROUND

The etiology and pathophysiological mechanisms of sudden sensorineural hearing loss (SSNHL) remain unclear, but it is generally believed to be associated with viral infections, vascular diseases, and autoimmune disorders. Considering that coronavirus disease 2019 (COVID-19) is promising candidates for SSNHL, we studied the immune cells changes by COVID-19 in patients with SSNHL.

METHODS

We collected data from 47 patients with SSNHL and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive. Patients were divided into ineffective or effective groups based on the degree of hearing recovery at discharge. Clinical information was collected and processed for both groups. Logistic regression models were used to determine the risk factors for an unfavorable prognosis in COVID-19-related SSNHL. Receiver operating characteristic (ROC) curves were used to estimate the predictive value.

RESULTS

There was statistically significant difference in C-reactive protein (CRP), auditory curve, degree decline, pretreatment hearing, posttreatment hearing, systolic blood pressure, diastolic blood pressure, total bilirubin, neutrophil-to-lymphocyte ratio (NLR), systemic immune-inflammation index (SII), indirect-bilirubin and platelet count between groups (p < 0.05). In the logistic regression model, high levels of SII and NLR were associated with treatment ineffectiveness, pre- and postcorrectively (both, p < 0.05). And ROC curve analysis showed higher AUC of 0.765 for SII, 0.697 for NLR,0.681 for CRP, and 0.553 for platelet-to-lymphocyte ratio (PLR) in predicting treatment outcomes.

CONCLUSION

The prognosis of COVID-19-related SSNHL was associated with inflammation. SII, NLR and CRP could serve as predictive markers of unfavorable outcomes in COVID-19-related SSNHL. SII may be considered an independent risk factor for poor prognosis in COVID-19-related SSNHL.

COVID-19 and Vestibular Symptoms and Assessment: A Review

BACKGROUND

The current pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in significant morbidity and mortality primarily associated with respiratory failure. However, it has also been reported that COVID-19 can evolve into a nervous system infection. The direct and indirect mechanisms of damage associated with SARS-CoV-2 neuropathogenesis could affect our sensory functionality, including hearing and balance.

SUMMARY

In order to investigate a possible association between SARS-CoV-2 viral infection and possible damage to the vestibular system, this review describes the main findings related to diagnosing and evaluating otoneurological pathologies.

KEY MESSAGES

The clinical evidence shows that SARS-CoV-2 causes acute damage to the vestibular system that would not leave significant sequelae. Recovery is similar to vestibular pathologies such as vestibular neuronitis and benign paroxysmal positional vertigo. Further basic science, clinical, and translational research is needed to verify and understand the short- and long-term effects of COVID-19 on vestibular function.

Experience of sudden sensorineural hearing loss following a mild COVID-19 infection

A woman in her 30s was referred to an otolaryngologist with an acute onset of aural fullness, noise sensitivity, unilateral sudden onset hearing loss, vertigo and tinnitus. She had a confirmed COVID-19 infection 5 weeks prior. A pure tone audiogram confirmed sensorineural hearing loss. MRI identified an empty sella of the pituitary gland and without an obvious cause for hearing loss. Oral prednisolone and betahistine were prescribed, and her audiovestibular symptoms slowly improved over the subsequent months. The patient continues to experience intermittent tinnitus.

A Prospective Study on Post Covid Sudden Onset Sensory Neural Hearing Loss and Its Recovery

Sudden sensorineural hearing loss (SSNHL) is a known complication of a number of viral infections, but there is little literature to date on its association to Corona virus disease 2019(COVID-19).This study aimed to investigate the incidence and recovery from SSNHL in post COVID-19 patients. A study was conducted in 6 months of duration at our tertiary care COVID dedicated hospital. Total 280 patients with age group of 12-70 years, laboratory confirmed COVID 19 positive patients having mild to moderate COVID symptoms were included. Patients were examined clinically along with all safety measures to analyze incidence and their recoveries from SSNHL by clinical examination and using Pure Tone Audiometry (PTA). Out of 280 patients the incidence of only SSNHL is 1.07% (3 patients) and SSNHL with tinnitus is 2.14%(6 patients).Total recovery(TR) regained in 2 patients of SSNHL, Partial recovery(PR) in 4 patients, Slight improvement(SI) in 1 patient and no recovery(NR) in 2 patients. The incidence of SSNHL in time of COVID 19 pandemic appears to be higher (3.2%) than before the pandemic (0.005%-0.16%). Incidence among younger age group and patients with no comorbidities has been also increased. In diagnosed case of SSNHL, early treatment with short term course of oral steroids and neuromodulator drugs are the mainstay treatment. Awareness of such non-specific presentation of COVID 19 patients is crucial and shared decision making with the patient and providing health care personnel is necessary for decreasing the hearing loss associated morbidity.

SARS-CoV-2 infection and multi-organ system damage: A review

The SARS-CoV-2 infection causes COVID-19, which has affected approximately six hundred million people globally as of August 2022. Organs and cells harboring angiotensin-converting enzyme 2 (ACE2) surface receptors are the primary targets of the virus. However, once it enters the body through the respiratory system, the virus can spread hematogenously to infect other body organs. Therefore, COVID-19 affects many organs, causing severe and long-term complications, even after the disease has ended, thus worsening the quality of life. Although it is known that the respiratory system is most affected by the SARS-CoV-2 infection, many organs/systems are affected in the short and long term. Since the COVID-19 disease simultaneously affects many organs, redesigning diagnostic and therapy policies to fit the damaged organs is strongly recommended. Even though the pathophysiology of many problems the infection causes is unknown, the frequency of COVID-19 cases rises with age and the existence of preexisting symptoms. This study aims to update our knowledge of SARS-CoV-2 infection and multi-organ dysfunction interaction based on clinical and theoretical evidence. For this purpose, the study comprehensively elucidates the most recent studies on the effects of SARS-CoV-2 infection on multiple organs and systems, including respiratory, cardiovascular, gastrointestinal, renal, nervous, endocrine, reproductive, immune, and parts of the integumentary system. Understanding the range of atypical COVID-19 symptoms could improve disease surveillance, limit transmission, and avoid additional multi-organ-system problems.

Evaluation of Disturbances in Hearing, Tinnitus, and Dizziness as Signs of COVID-19 Infection

BACKGROUND

There have been reports and studies indicating audiovestibular disturbances in COVID-19 patients with variations in the percentage of sensorineural hearing loss (SNHL). The purpose of this study is to compare the incidence of newly diagnosed SNHL, sudden idiopathic hearing loss (SIHL), tinnitus, and vestibular disturbances between infected and uninfected patients, as well as to identify population groups at risk.

METHODS

This study used TriNetX to obtain statistics on COVID-19 (+) and COVID-19 (-) patients from 61 healthcare organizations. Propensity score with 1:1 matching was used to control confounding variables. This study evaluated the relative risk of developing audiovestibular disturbances up to 1 month after a COVID-19 test and further investigated the incidence in COVID-19 (+) subset groups.

RESULTS

Between COVID-19 (+) and COVID-19 (-) patients who had an audiogram, there was no statistically significant difference in SNHL or SIHL (SNHL: relative risk [RR] = 0.69, 95% confidence interval [CI] = 0.46-1.04; SIHL: RR = 1.00, 95% CI = 0.42-2.40). Race/ethnicity or specified comorbidity did not affect the incidence of SNHL or SIHL. There was a statistically significant difference in tinnitus and vestibular disturbances between the COVID-19 (+) and the COVID-19 (-) groups (RR = 1.29, 95% CI = 1.01-1.66; RR = 2.33, 95% CI = 2.19-2.48).

CONCLUSION

New onset hearing loss is not more common in patients with a positive COVID-19 test than those with a negative COVID-19 test. Audiologic evaluation is needed to verify reported hearing disturbances. Although statistically significant in specific population groups, tinnitus and vestibular disturbances may not be clinically significant due to the low incidence.

Monitoring of Auditory Function in Newborns of Women Infected by SARS-CoV-2 during Pregnancy

BACKGROUND

Gestational SARS-CoV-2 infection can impact maternal and neonatal health. The virus has also been reported to cause newborn sensorineural hearing loss, but its consequences for the auditory system are not fully understood.

OBJECTIVE

The aim of this study was to evaluate the impact of maternal SARS-CoV-2 infection during pregnancy on newborn' hearing function during the first year of life.

METHODS

An observational study was conducted from 1 November 2020 to 30 November 2021 at University Modena Hospital. All newborns whose mother had been infected by SARS-CoV-2 during pregnancy were enrolled and underwent audiological evaluation at birth and at 1 year of age.

RESULTS

A total of 119 neonates were born from mothers infected by SARS-CoV-2 during pregnancy. At birth, five newborns (4.2%) presented an increased threshold of ABR (Auditory Brainstem Evoked Response), but the results were confirmed only in 1.6% of cases, when repeated 1 month later, while the ABR thresholds in all other children returned to normal limits. At the 1-year follow-up, no cases of moderate or severe hearing loss were observed, while concomitant disorders of the middle ear were frequently observed.

CONCLUSIONS

Maternal SARS-CoV-2 infection, regardless of the trimester in which it was contracted, appears not to induce moderate or severe hearing loss in infants. It is important to clarify the possible effect of the virus on late-onset hearing loss and future research is needed.

The Incidence of Sudden Sensorineural Hearing Loss (SSNHL) in COVID-19 Patients in Tertiary Care Referral Units

COVID-19 is a new pandemic infectious disease that emerged in Wuhan, China, at the end of 2019. We aimed to evaluate the sudden sensorineural hearing loss (SSNHL) prevalence after COVID-19 infection or even vaccination. This is a two-center retrospective, observational cross-sectional study performed at tertiary care referral Audiovestibular Medicine Units at the period between August 1, 2020, and October 31, 2021. All SSNHL patients diagnosed in a period of a month with COVID-19 or vaccinated with a COVID-19 vaccine were included in this study. Fifty-three cases with confirmed COVID-19 and one patient vaccinated with a COVID-19 vaccine 1 week before, who reported sudden sensory neural hearing loss, were included in this study. Forty-eight patients had unilateral hearing loss and 6 patients had bilateral hearing loss. Forty-nine patients had typical COVID-19 symptoms; one patient discovered them after complaining of anosmia and ageusia and one patient after COVID-19 vaccination; and three patients were complaining only from hearing loss and had a PCR test for nasopharyngeal swabs to prove infection. Different degrees of SSNHL ranged from mild to severe and most of the patients had severe hearing loss. With more patients, COVID-19 may be a potential factor in sudden sensorineural hearing loss. It should be kept in mind that SSNHL may be the only indicator used to identify COVID-19 cases.

Sudden Sensorineural Hearing Loss in the COVID-19 Pandemic: A Systematic Review and Meta-Analysis

INTRODUCTION

Accumulating data indicate that patients with COVID-19 could be affected by sudden sensorineural hearing loss (SSNHL). The aim of the study was to analyze the epidemiological and clinical trend of SSNHL occurrence during the COVID-19 pandemic by applying a systematic review and meta-analysis approach.

METHODS

PubMed, Scopus, Web of Science, ScienceDirect, and Cochrane databases were searched.

RESULTS

The seven included studies had adequate relevance to the topic and the quality was fair. The mean age at SSNHL onset ranged from 39.23 to 62.18 years during the pandemic year period (PYP); a meta-analysis of four studies comparing these data with those of previous periods in the same institutions found a younger age during the PYP (pooled mean -0.2848). The heterogeneity was high (76.1935%) and no frank asymmetry was observed in the funnel plot. The SARS-CoV-2 positivity rate of SSNHL patients ranged from 0% to 57.53%. Standard steroid treatments were applied without significant adverse effects. Comprehensively, hearing improvement was achieved for more than half of the cases. No studies reported long-term follow-up data.

CONCLUSIONS

Further prospective analyses on large series and a long-term follow up on COVID-related SSNHL cases are necessary to address the open questions regarding the causative link between COVID-19 infection and SSNHL.

Comparative Study of Audiovestibular Symptoms between Early and Late Variants of COVID-19

Audiovestibular symptoms during the acute phase of the corona virus disease 2019 (COVID-19), have been reported for earlier waves of the pandemic, while no studies investigated nor compared audiovestibular manifestations during subsequent waves of COVID-19. In the current study, we aimed to compare the occurrence of audiovestibular symptoms associated with COVID-19 between the alpha/beta, delta, and omicron variants. An online questionnaire was distributed to individuals with confirmed test results for COVID-19. We asked participants to report whether they experienced audiovestibular symptoms during the acute phase of the disease. The study included 939 participants; 120 un-infected controls and infected participants during alpha/beta (n = 301), delta (n = 102), and omicron (n = 416) predominance periods. Self-reported audiovestibular symptoms were found to be statistically significantly different between un-infected controls and COVID-19 infected individuals in all analyzed variants. Furthermore, our results showed no significant differences in audiovestibular symptoms among individuals infected during alpha/beta, delta, and omicron waves. Although individuals infected during the delta variant predominance period reported higher percentages of audiovestibular symptoms (ranging from 11.8% to 26.5% for auditory symptoms and from 12.7% to 34.3% for vestibular symptoms) than for the alpha/beta (ranging from 6.3% to 18.9% for auditory symptoms and 8.3% to 29.9% for vestibular symptoms) and omicron (ranging from 9.6% to 21.2% for auditory and 12.5 to 29.1% for vestibular symptoms) variants, this did not achieve statistical significance. With regards to auditory symptoms, the most commonly reported symptoms were aural fullness followed by hearing loss and tinnitus. With regards to vestibular symptoms, dizziness was the most commonly reported symptom followed by vertigo and unsteadiness. Logistic regression revealed that experiencing auditory symptoms were associated with other neurological symptoms, back and joint pain, and chest pain as COVID-19 symptoms. Vestibular symptoms were associated with anemia, gender, fatigue, headache, and breathing difficulties. In conclusion, our study shows that audiovestibular symptoms are common during the acute phase of early and late COVID-19 variants with no significant differences between them.

Update on Findings about Sudden Sensorineural Hearing Loss and Insight into Its Pathogenesis

Sudden sensorineural hearing loss (SSNHL) is routinely encountered and is one of the most common emergent diseases in otolaryngology clinics. However, the etiology of SSNHL remains unclear. Due to the inaccessibility of the living human inner ear for biopsy, studies investigating the etiology of SSNHL have been performed by analyzing data obtained from examinations using peripheral blood or imaging. We updated the findings obtained from serological, magnetic resonance imaging, genetic, and viral examinations to reveal the etiology of SSNHL. Regarding viral examination, we focused on sensorineural hearing loss associated with coronavirus disease (COVID-19) because the number of correlated reports has been increasing after the outbreak. The updated findings revealed the following three possible mechanisms underlying the development of SSNHL: thrombosis and resulting vascular obstruction in the cochlea, asymptomatic viral infection and resulting damage to the cochlea, and cochlear inflammation and resulting damage to the cochlea. Thrombosis and viral infection are predominant, and cochlear inflammation can be secondarily induced through viral infection or even thrombosis. The findings about sensorineural hearing loss associated with COVID-19 supported the possibility that asymptomatic viral infection is one of the etiologies of SSNHL, and the virus can infect inner ear tissues and directly damage them.

The pharmacological treatment of acute vestibular syndrome

Acute vestibular syndrome (AVS) represents a clinical picture that involves urgent management due to the important procession of symptoms accompanying the event, which can be positively or negatively influenced by therapeutic choices and intervention timing. This forces a differential diagnosis and therapeutic choices to be made in conditions that are not always favorable and often not in the specialist field. In this work, we will examine in detail the pharmacological therapeutic possibilities, correlating them to the differential and, as far as possible, to the etiological diagnosis. In particular, the pharmacological possibilities for the two main conditions we can face will be investigated, namely, vestibular neuritis and posterior circulation stroke.

Cochleovestibular findings linked to COVID-19: A scoping review for clinical care planning in South Africa

Background

On 30 January 2020, the World Health Organization (WHO) officially declared an outbreak of the coronavirus disease 2019 (COVID-19) to be a global health emergency. Research has focused on the impact and response to life-threatening symptoms of COVID-19 across the lifespan; however, there is a need to investigate the effects of COVID-19 on the cochleovestibular system, as viral infections are known to impact this system. This is particularly important for contexts where resources are limited and prioritisation of resources requires strong risk versus benefit evaluations.

Objective

Therefore, the purpose of this scoping review was to investigate published evidence on the impact of COVID-19 on the cochleovestibular system across the lifespan in order to allow for strategic clinical care planning in South Africa, where capacity versus demand challenges exist.

Methods

Electronic bibliographic databases such as CINAHL, EBSCOHost, MEDLINE, ProQuest, PubMed, Scopus and ScienceDirect were searched for peer-reviewed publications between January 2020 and January 2022. These had to be published in English and related to the impact of COVID-19 on the cochleovestibular system, where the question was: ‘what evidence has been published on the impact of COVID-19 on the cochleovestibular system?’ Review selection and characterisation was performed by the researcher with an independent review by a colleague using pretested forms.

Results

Of a total of 24 studies that met the inclusion criteria, the current scoping review revealed limited conclusive published evidence linking COVID-19 to permanent hearing function symptoms. Current evidence supports the possibility of COVID-19, similar to other viral infections in adults, impacting the cochleovestibular system and causing tinnitus, vertigo and sudden sensorineural hearing loss (SSNHL), with the symptoms being generally temporary and resolving either partially or completely following therapy with steroids, with very inconclusive findings in the paediatric population.

Conclusion

These findings raise global implications for properly designed studies, which include longitudinal follow-up of cases across the lifespan, examining this link with some focus on establishing the pathophysiologic mechanisms at play as well. In the meanwhile, current findings raise the value of polymerase chain reaction (PCR) testing for all patients presenting with unexplained cochleovestibular symptoms during the pandemic, as these may be the only presenting symptoms indicating COVID-19, thus requiring careful treatment and management.

The New Coronavirus Infection (COVID-19) and Hearing Function in Adults

In this study, we assessed the impact of COVID-19 on the hearing function in adults. A total of 161 subjects were examined, and the results of a previous audiological examination of 24 patients were reviewed. Pure tone audiometry, impedancemetry, speech audiometry in quiet and noise, the Binaural Fusion Test, the dichotic digits test, and a cognitive status examination were performed. A total of 81% of patients complained about hearing disorders, and 43% noted memory impairment. According to pure tone audiometry, 24% of the subjects had normal hearing, while 76% had some degree of hearing loss. No significant changes in hearing thresholds were found in comparison with audiological examinations performed before COVID-19. Disorder of monosyllabic words’ intelligibility in quiet was found in 33% of patients, and in 42% in noise, along with low indicators in the dichotic digits test in 54% of patients. Moreover, 71% of patients had low scores on the MoCA scale that indicated cognitive impairment. Conclusions: The deterioration of speech test scores in patients after COVID-19 can occur due to central auditory processing disorders (CAPD), memory impairment, or changes in cognitive status in general.

Sensorineural Hearing Loss Post-COVID-19 Infection: An Update

The course of COVID-19 infection may be complicated by a variety of neurological manifestations. Since the inner ear is vulnerable to viruses, sensorineural hearing loss (SNHL) has been reported to occur following the SARS-CoV-2 infection, often resulting in long-term morbidity and worsening the quality of life. The interest in how the virus affects the inner ear has gradually increased since the pandemic’s spread, but little is still known about the SNHL potentially caused by SARS-CoV-2. The aim of this paper is to evaluate the possible association between SNHL and COVID-19 infection, through a systematic literature review. Currently available data suggest that SARS-CoV-2 may hamper cochlear function; however, available reports are still limited. Large cohort and prospective studies are necessary to evaluate the long-term effects of this viral infection in the inner ear.

COVID-19 and Sudden Sensorineural Hearing Loss: A Systematic Review

A growing body of evidence suggests that patients with the 2019 Coronavirus disease (COVID-19) have a risk of developing sudden sensorineural hearing loss (SSNHL). The pathogenesis of COVID-19-related SSNHL remains unclear. This systematic review examined whether COVID-19 causes an increased incidence of SSNHL and the clinical characteristics of patients with COVID-19-related SSNHL according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. SSNHL usually developed between a few days and 2 months after the diagnosis of COVID-19, and a proportion of patients developed it before the diagnosis of COVID-19. The literature is inconsistent regarding whether COVID-19 causes an increased incidence of SSNHL, and this matter remains unclear. This review included 23 patients with COVID-19-related SSNHL, all adult patients with an average age of 43.1 years. Of these patients, 60.9% had accompanying tinnitus symptoms. Glucocorticoids are the preferred medication to treat COVID-19-related SSNHL. Intratympanic administration may be considered to reduce the side effects of the drug. Hearing tests are suggested when hearing loss is suspected in COVID-19 individuals, and if SSNHL is detected, prompt and aggressive treatment is vital. Large-scale, multicenter research on the pathophysiology, treatment, and prognosis of COVID-19- related SSNHL should be conducted in the future.

Audiovestibular Disorders after COVID-19 Vaccine: Is There an Association?

The SARS-CoV-2 vaccination campaign is probably one of the most historic public hygiene measures in modern medicine. The drama of the pandemic has forced the scientific community to accelerate the development and commercialization of vaccines, thereby enhancing the phases of active surveillance. Among the adverse events following immunization (AEFI) reported, those of an audiovestibular interest, such as sudden sensorineural hearing loss (SSNHL), tinnitus, dizziness, and vertigo, constitute a very small percentage. There are many plausible etiological hypotheses, and scientific research needs to pay more attention to the correct collection of data, which up until now have often been inadequate and fragmented, on which to base future studies. SSNHL, new onset tinnitus, vertigo, and dizziness require a prompt evaluation, while the proposed treatment is the same as it is for events unrelated to vaccination. These are uncommon adverse events, and the risk rates for these diseases have not increased in conjunction with the COVID-19 vaccinations, therefore there is no justification of any hesitation towards the vaccination campaign.

Vestibular Neuritis Following COVID-19 Vaccination: A Retrospective Study

Objective

To determine if the COVID-19 vaccine can cause vestibular neuritis (VN).

Design

Retrospective study.

Setting

Vertigo outpatient clinic of the Department of Otolaryngology JR Tokyo General Hospital.

Participants:

378 patients who presented at the Vertigo clinic between July 2018 and March 2022

Results

23 out of 378 cases were diagnosed with vestibular neuritis. There was a significant seasonal bias of the onset of VN in 2021-3Q compared to other seasons. All 7 patients diagnosed with VN whose onset was 2021-3Q and 2021-4Q had received the BNT162b2 (Pfizer-BioNTech) vaccine within the previous 3 months and one patient diagnosed with VN whose onset was 2022-1Q had a history of COVID-19 infection six months earlier.

Conclusions

VN should be recognized as one of the side-effects of the BNT162b2 COVID-19 vaccination.

Vestibular Cochlear Manifestations in COVID-19 Cases

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a high transmissible infectious disease that primarily impacts the respiratory system and leads to death as it worsens. Ever since the World Health Organization declared the disease as a global pandemic, the pathophysiology, clinical manifestations, and disease prognosis has been discussed in various literature. In addition to impaired respiratory health, the symptoms also indicated the involvement of the cardiovascular and neurological system after SARS-CoV-2 infection. Despite the pulmonary, cardiovascular, and neurological complications, many reports also revealed the prevalence of vestibulocochlear symptoms like dizziness, vertigo, vestibular neuritis, sudden sensorineural hearing loss, and tinnitus. Though many clinical reports and scientific reviews reported the vestibular and cochlear impairments associated with coronavirus disease 2019 (COVID-19) infection, the underlying pathological mechanisms are still unclear and unexplored. In this review, we discussed the published clinical reports, research articles, and literature reviews related to vestibulocochlear manifestations following SARS-CoV-2 infections. We also summarized the current knowledge about the prevalence, epidemiological and clinical features, and potential pathological mechanisms related to vestibular and cochlear manifestations resulting from COVID-19 infections.

Sudden sensorineural hearing loss after covid-19 vaccine; A possible adverse reaction?

Background

Sudden Sensorineural Hearing Loss (SSNHL) is a relatively rare symptom after immunisation from commonly used vaccines such as rabies, hepatitis B, measles and H1N1 and it could be an occasional symptom of COVID-19, even in mild manifestations of the disease.

Case report

We describe the case of a 57-year-old patient that reported SSNHL and tinnitus in his right ear 2 days after the inoculation of the Oxford-AstraZeneca (VAXZEVRIA) Covid-19 vaccine. The patient almost fully recovered after therapy and was referred to a long term follow-up program.

Conclusion

The current report underlines the importance to consider SSNHL as a possible rare adverse effect of the Covid-19 vaccine and take in account this possibility to promptly proceed with diagnosis and treatment of suspect cases.