Immune-mediated audiovestibular disorders in the paediatric population: A review

Unilateral Sensorineural Hearing Loss in Children Associated With Sjögren's Syndrome

The occurrence of unilateral sensorineural hearing loss (SNHL) during school age is relatively rare and accounts for approximately 6% of all deafness in childhood. We present two cases involving children who were diagnosed with SNHL associated with Sjögren's syndrome (SS). Case 1: An eight-year-old girl with an approximately two-year clinical history of gradual hearing loss was diagnosed with SNHL associated with SS based on histological findings of inflammation in the salivary glands and the presence of serum anti-Sjögren's syndrome-A antibody. Case 2: An eight-year-old boy with acute idiopathic thrombocytopenic purpura in whom unilateral hearing loss, which was not associated with any problems in daily life, was detected during hospitalization and who was finally diagnosed with SNHL and SS. Steroid treatment was ineffective for both patients. The previously unrecognized combination of SNHL with SS should be considered in the diagnosis of unilateral SNHL, even in children.

Hearing evaluation with ABR in pediatric patients with celiac disease

BACKGROUND/AIMS

Celiac disease (CD) is an autoimmune and genetic disease that is triggered by gluten intolerance. We aimed to investigate whether Celiac disease have any effect on Auditory Brainstem Response (ABR) waves compare to a healthy control group, and present its association with sensorineural hearing loss (SNHL).

MATERIALS AND METHODS

Thirty-eight patients aged 2 to 16 years old were included in the study. The patients had confirmed diagnosis of Celiac disease through duodenal biopsies and transglutaminase Antibody (Ab) (+). The control group consisted of 18 children aged 3 to 17 years old who were all admitted to the pediatric gastroenterology department due to complaints of constipation and transglutaminase Ab (-).All children underwent Auditory-Brain-Stem-Evoked Responses (ABR). The data were gathered using click stimulus at 10/s frequency 90dB HL.

RESULTS

The results of ABR examination did not show any difference between the patient group and control group as regards the latency of the waves I, III, V. No difference was observed between the two groups in the interpeak latecies I-III, I-V and III-V. None of the patients was observed to have clinical hearing loss.

DISCUSSION

The exact pathogenesis of neurological damages observed in Celiac disease is still unknown. Humoral immune mechanisms are the most frequently attributed cause.

CONCLUSION

Although no significant difference was found in hearing values between the study group and healthy control group, there is a need for further research on this subject.

MRI of the Internal Auditory Canal, Labyrinth, and Middle Ear: How We Do It

MRI is firmly established as an essential modality in the imaging of the temporal bone and lateral skull base. It is used to evaluate normal anatomic structures, evaluate for vestibular schwannomas, assess for inflammatory and/or infectious processes, and detect residual and/or recurrent cholesteatoma. It is also extensively used in pre- and postoperative evaluations, particularly in patients with vestibular schwannomas and candidates for cochlear implantation. Nevertheless, despite the widespread use of MRI for these purposes, many radiologists remain unfamiliar with the complex anatomy and expected imaging findings with such examinations. The purpose of this review is to provide an overview of the most useful MRI sequences for internal auditory canal and labyrinthine imaging, review the relevant anatomy, and discuss the expected appearances of the most commonly encountered pathologic entities. In addition, the features at pre- and postprocedural MRI will be discussed to help ensure that diagnostic radiologists may be of greatest use to the ordering physicians. © RSNA, 2020.

Bilateral Labyrinthine and Internal Auditory Canal Enhancement in an Infant With Severe Labyrinthine Dysplasia: A Previously Unreported Phenomenon

OBJECTIVE

To describe a novel case of congenital profound bilateral sensorineural hearing loss in a patient with bilateral nodular internal auditory canal and labyrinthine enhancement and temporal bone dysplasia.

PATIENTS

A 76-day-old female was referred to the authors' center for evaluation of congenital deafness. Behavioral observations and objective audiometric evaluation demonstrated bilateral profound sensorineural hearing loss and a comprehensive multidisciplinary evaluation identified compound heterozygous pathogenic variants in MYO7A, a gene associated with Usher Syndrome Type 1B or DFNB2. Computed tomography and contrast-enhanced magnetic resonance imaging studies demonstrated bilateral temporal bone anomalies with unique middle and inner ear malformations, as well as unique contrast enhancement in the membranous labyrinth, internal auditory canals, and cranial nerves, which have not been previously described with MYO7A variants.

INTERVENTIONS

Given the potential risk for progressive bilateral labyrinthitis ossificans, bilateral simultaneous cochlear implantation was performed at 4 months of age.

MAIN OUTCOME MEASURES

Subsequent audiologic follow up after implantation shows significantly improved access to auditory information and increased vocalizations. At last testing, speech and language skills for both receptive and expressive language abilities were found to be commensurate with her chronological age.

CONCLUSION

We report a novel presentation and imaging findings of congenital bilateral profound sensorineural hearing loss in a patient with nodular internal auditory canal and labyrinthine enhancement and coexisting inner ear dysplasia. Despite the multiple radiologic abnormalities, the patient has demonstrated good benefit from cochlear implantation. Future study of rare variants of congenital deafness, such as this, is critical toward defining new disease processes and determining optimal treatment.

Mean platelet volume: is it a predictive parameter in the diagnosis of sudden sensorineural hearing loss?

The mean platelet volume (MPV) is associated with increased platelet reactivity and increased atherothrombosis. High MPV values are a risk factor for thrombotic vascular diseases. Our aim was to investigate whether a relationship exists between sudden sensorineural hearing loss (SSHL) and a high MPV value. The records of 46 patients who were admitted to the ENT (ear nose throat) ward for SSHL and received medical treatment and 46 patients in a control group were retrospectively screened. The correlation among the levels of the MPV, the number of platelets, and SSHL were evaluated in the two groups. The ages, genders, and the platelet count values of the patients showed a normal distribution in both groups. No significant difference was found for the MPV values between the groups. The MPV is not a predictive parameter in the diagnosis of SSHL.

Expression of Autoantibodies in Patients with Sudden Sensorineural Hearing Loss

Objectives:

The aim of this study was to establish the expression rate of autoimmunity in patients with sudden sensorineural hearing loss and to determine whether a positive marker is associated with a higher rate of hearing recovery after steroid treatment.

Methods:

A prospective study was performed on 137 patients who experienced sudden sensorineural hearing loss and underwent immunoserologic investigations. Autoantibodies evaluated on the day of admission included anti-double-stranded DNA, rheumatoid factor, antiphospholipid immunoglobulins G and M, antinuclear antibody, and complements C3 and C4.

Results:

Of 137 patients, 75 were male and 62 were female (mean age, 45.1 years). Hearing loss was found on the left side in 61 patients and on the right side in 76 patients. Elevation of at least 1 autoantibody or abnormal complement levels were found in 80 patients (58%), and abnormalities of 2 or more antibodies were found in 28 (20%). There were no statistically significant correlations between autoantibody abnormalities and age, initial hearing level, or positive treatment response.

Conclusions:

There is no clear evidence of a correlation between autoimmunity and hearing improvement in patients with autoantibody abnormalities. A high (but not significant) expression rate of autoantibody abnormality and complement level was seen in patients with sudden sensorineural hearing loss.

The evaluation of hearing loss in children with celiac disease

BACKGROUND AND AIMS

Celiac disease (CD) is an autoimmune enteropathy. The disease may be presented with extraintestinal manifestations including neurological findings. Epilepsy and ataxia are well known neurological disorders in CD. But there are very limited numbers of reports on sensory-neural hearing loss in CD in the literature. The aim of this study was to investigate the hearing functions in children with newly diagnosed CD.

MATERIALS AND METHODS

Ninety-seven (194 ears) [56 girls, 41 boys (age range: 1.5-17 years)] newly diagnosed celiac disease patients and 85 sex and age-matched controls (170 ears) were included in this study. Hearing function was assessed by pure-tone audiometry, speech audiometry, tympanometry and otoacoustic emissions measurements.

RESULTS

No significant difference were found between the patients and control groups measurements including the pure-tone audiometry, speech audiometry, tympanometry and otoacoustic emissions No significant difference was found for pure-tone audiometry, speech audiometry, tympanometry and otoacoustic emissions measurements in celiac patients according to the Marsh-Oberhuber classification (P>0.05).

CONCLUSIONS

Our results showed that hearing functions of children with newly diagnosed CD were similar to healthy controls.

Corticosteroid therapy for hearing and balance disorders

This review addresses the current status of steroid therapies for hearing and vestibular disorders and how certain misconceptions may be undermining the efficacy in restoring normal ear function, both experimentally and clinically. Specific misconceptions addressed are that steroid therapy is not effective, steroid-responsive hearing loss proves an underlying inflammatory problem in the ear, and steroids only have application to the hearing disorders listed below. Glucocorticoid therapy for hearing and balance disorders has been employed for over 60 years. It is recommended in cases of sudden hearing loss, Meniére's disease, immune-mediated hearing loss, and any vestibular dysfunction suspected of having an inflammatory etiology. The predominant steroids employed today are dexamethasone, prednisone, prednisolone, and methylprednisolone. Despite years of use, little is known of the steroid responsive mechanisms in the ear that are influenced by glucocorticoid therapy. Furthermore, meta-analyses and clinical study reviews occasionally question whether steroids offer any benefit at all. Foremost in the minds of clinicians is the immune suppression and anti-inflammatory functions of steroids because of their efficacy for autoimmune hearing loss. However, glucocorticoids have a strong binding affinity for the mineralocorticoid (aldosterone) and glucocorticoid receptors, both of which are prominent in the ear. Because the auditory and vestibular end organs require tightly regulated endolymph and perilymph fluids, this ion homeostasis role of the mineralocorticoid receptor cannot be overlooked in both normal and pathologic functions of the ear. The function of the glucocorticoid receptor is to provide anti-inflammatory and antiapoptotic signals by mediating survival factors.

Vascular Pathophysiology in Hearing Disorders

The inner ear vasculature is responsible for maintenance of the blood-labyrinth barrier, transport of systemic hormones for ion homeostasis, and supplying nutrients for metabolic functions. Unfortunately, these blood vessels also expose the ear to circulating inflammatory factors resulting from systemic diseases. Thus, while the inner ear blood vessels are critical for normal function, they also are facilitating pathologic mechanisms that result in hearing and vestibular dysfunction. In spite of these numerous critical roles of inner ear vasculature, little is known of its normal homeostatic functions and how these are compromised in disease. The objective of this review is to discuss the current concepts of vascular biology, how blood vessels naturally respond to circulating inflammatory factors, and how such mechanisms of vascular pathophysiology may cause hearing loss.

Stem cell treatment for patients with autoimmune disease by systemic infusion of culture-expanded autologous adipose tissue derived mesenchymal stem cells

Prolonged life expectancy, life style and environmental changes have caused a changing disease pattern in developed countries towards an increase of degenerative and autoimmune diseases. Stem cells have become a promising tool for their treatment by promoting tissue repair and protection from immune-attack associated damage. Patient-derived autologous stem cells present a safe option for this treatment since these will not induce immune rejection and thus multiple treatments are possible without any risk for allogenic sensitization, which may arise from allogenic stem cell transplantations. Here we report the outcome of treatments with culture expanded human adipose-derived mesenchymal stem cells (hAdMSCs) of 10 patients with autoimmune associated tissue damage and exhausted therapeutic options, including autoimmune hearing loss, multiple sclerosis, polymyotitis, atopic dermatitis and rheumatoid arthritis. For treatment, we developed a standardized culture-expansion protocol for hAdMSCs from minimal amounts of fat tissue, providing sufficient number of cells for repetitive injections. High expansion efficiencies were routinely achieved from autoimmune patients and from elderly donors without measurable loss in safety profile, genetic stability, vitality and differentiation potency, migration and homing characteristics. Although the conclusions that can be drawn from the compassionate use treatments in terms of therapeutic efficacy are only preliminary, the data provide convincing evidence for safety and therapeutic properties of systemically administered AdMSC in human patients with no other treatment options. The authors believe that ex-vivo-expanded autologous AdMSCs provide a promising alternative for treating autoimmune diseases. Further clinical studies are needed that take into account the results obtained from case studies as those presented here.

Pediatric sensorineural hearing loss, part 2: syndromic and acquired causes

This article is the second in a 2-part series reviewing neuroimaging in childhood SNHL. Previously, we discussed the clinical work-up of children with hearing impairment, the classification of inner ear malformations, and congenital nonsyndromic causes of hearing loss. Here, we review and illustrate the most common syndromic hereditary and acquired causes of childhood SNHL, with an emphasis on entities that demonstrate inner ear abnormalities on cross-sectional imaging. Syndromes discussed include BOR syndrome, CHARGE syndrome, Pendred syndrome, Waardenburg syndrome, and X-linked hearing loss with stapes gusher. We conclude the article with a review of acquired causes of childhood SNHL, including infections, trauma, and neoplasms.

Role of developmental immunotoxicity and immune dysfunction in chronic disease and cancer

The developing immune system is among the most sensitive targets for environmental insult and risk of chronic disease including cancer. Developmental immunotoxicity (DIT)-associated health risks include not only pediatric diseases like childhood asthma and type 1 diabetes, but also multi-disease "patterns" of conditions linked to the initial immune dysfunction. DIT contributes to ever-increasing health care costs, increasing reliance on drugs and reduced quality of life. Drug discovery efforts using cutting-edge immunology produce effective tools for management of allergic, autoimmune and inflammatory diseases; in stark contrast, required immunotoxicity testing clings to an outdated understanding of the immune system and its relationship to disease. As currently required, immune safety evaluation of drugs and chemicals lacks the capability of protecting against the most prevalent pediatric immune dysfunction-based diseases. For this reason, mandatory and relevant DIT testing is needed for all drugs and chemicals where pregnant women and children are at risk.

Unravelling autoimmune pathogenesis by screening random peptide libraries with human sera

The incidence of autoimmunity is increasing worldwide. The long preclinical period of autoimmune disorders is characterised by an enhanced exposure over time of autoreactive T cells to an increased number of autoantigenic determinants and autoantibodies production. The discovery of novel autoimmune-disease related epitopes is a task that remains extremely challenging in order to establish predictive and preventive strategies of the disease onset. In this Opinion article we highlight the contribution of screening combinatorial random peptide libraries with patients sera in unravelling the etiopathogenesis of autoimmunity.