Do antithyroid antibodies affect hearing outcomes in patients with pediatric euthyroid Hashimoto's thyroiditis?

Audiological evaluation (128-20,000Hz) in women with autoimmune thyroiditis: The role of antibodies vs. l-thyroxine deficiency

BACKGROUND AND AIM

Although sensorineural hearing loss may have different aetiologies, we focused on autoimmune hearing loss since it may be reversible with corticosteroid therapy; this entity is sometimes associated with systemic autoimmune diseases. Hashimoto's thyroiditis or chronic autoimmune thyroiditis shows antibodies and may be harmful to hearing thresholds regardless of hypothyroidism effect. To date this effect has not been sufficiently studied and never with extended high frequencies. The aim of this work is to study by age groups whether hearing thresholds in the human auditory range (128-20,000Hz) are affected in Hashimoto's disease.

MATERIALS AND METHODS

Two groups of 128 patients affected by Hashimoto's thyroiditis were included. First group: patients with pathological antithyroid antibodies who do not need L-thyroxine treatment. Second group: patients controlled with L-thyroxine substitutive treatment. Audiometric threshold study comparing between the groups of patients and a group of 209 controls was performed. All patients underwent complete otorhinolaryngological examination, antithyroid antibodies, TSH, T₃ and T₄ blood levels, tympanometry, conventional pure-tone audiometry, and extended-high-frequency audiometry.

RESULTS

All patients were women. Both groups showed worst audiometric thresholds than the control group; both study groups showed worse hearing than controls, this difference was statistically significant in all frequencies. In the 8-20kHz frequency range, this difference was more than 10dB, and in the 9-16kHz and 20kHz range this difference was more than 20dB. When separated by age groups, in younger subjects (20-29 years) these differences were found in all frequencies, except for conversational frequencies (500-4,000Hz); between 30 and 49 years the difference is statistically significant in all frequencies; and from 50 to 69 years differences are found, especially in the conversational frequencies.

CONCLUSIONS

This first work studying the human auditory range in the chronic autoimmune thyroiditis or Hashimoto's thyroiditis confirms that hearing loss related to the autoimmune disorder predominates at extended-high-frequencies initially. But ends up involving all frequencies in pure-tone conventional audiometry, then it may be detected in routine clinical tests. These results support the role of extended-high-frequencies audiometry to diagnose subclinical hearing loss in patients affected by Hashimoto's thyroiditis.

Hearing Impairment and Audiological Alterations in Euthyroid Hashimoto's Thyroiditis

INTRODUCTION

Hearing loss may be associated with autoimmune diseases, but it was less studied in Hashimoto's thyroiditis (HT). We aimed to evaluate hearing impairment and audiological alterations in adults with euthyroid HT.

METHODS

Adult patients with euthyroid HT (normal thyroid functions, positive antithyroid peroxidase (anti-TPO)/anti-thyroglobulin, and sonographic findings) were compared with controls. We excluded pregnant or older patients (>40 years), those with a history of otological/audiological disease or surgery, otitis media, acoustic trauma, chronic illnesses, use of alcohol, cigarette, medications, rheumatoid factor, antinuclear, antimitochondrial, antiparietal, antineutrophil cytoplasmic, anti-smooth muscle, or antigliadin antibodies, abnormal biochemical or otological findings. Tympanometry which indicates tympanic peak pressure (TPP, daPa), acoustic reflex testing (ART), pure-tone average (PTA), and transient evoked otoacoustic emission (TEOAE) were performed. We grouped the participants according to ART (positive/negative), TEOAE (normal/undetected), and PTA (≤20/>20 decibel).

RESULTS

Air conduction thresholds on the right ear at 500, 4,000, 6,000, and 8,000 Hz, PTA, and the left ear at 250, 4,000, 6,000, and 8,000 Hz were higher in euthyroid HT (n = 36) than in controls (n = 40) (p < 0.05). We found less negative TPP and a higher ratio of negative ART in euthyroid HT (p < 0.05). Euthyroid HT predicted undetected TEOAE and increased hearing threshold on the right ear at 500 and 8,000 Hz (p < 0.001). TEOAE detected audiological abnormality at a higher rate. Anti-TPO was positively correlated with TPP and air conduction thresholds, except the right ear at 8,000 Hz.

DISCUSSION/CONCLUSION

Hearing and audiological tests may be impaired in euthyroid HT. We recommend close monitoring of audiological functions in these patients. TE-OAE more specifically indicates audiological abnormality.

Dysfunction of the Auditory System in Children With Hypothyroidism: A Systematic Review and Meta-Analysis

OBJECTIVE

To examine the prevalence of hearing impairment in children with hypothyroidism, and to characterize clinical and subclinical hearing loss by examining cochlear function, auditory brainstem pathways, and integration of the auditory system as a whole.

DESIGN

An electronic search was conducted using PubMed, Scopus, and Cochrane Library databases. This systematic review was performed in accordance with the PRISMA guidelines. Original observational studies that utilized audiological tests for auditory system evaluations in hypothyroidism were included. A total of 2004 studies were found in the search, with 23 studies meeting the inclusion criteria.

RESULTS

The pooled prevalence of hearing loss was 16.1% [95% confidence interval 10.7, 22.4] for children with congenital hypothyroidism. Hearing thresholds at pure-tone averages (0.5-2 kHz) were 1.6 dB [95% confidence interval 1.7, 4.8] higher for children with hypothyroidism compared to age-matched controls. Cochlear dysfunction was detected at middle frequencies (1-3 kHz) by otoacoustic emission testing, indicating abnormalities of hair cell function or cochlear integration. Retrocochlear involvement was detected on auditory brainstem response (ABR), with prolonged Wave I indicating a peripheral conduction abnormality localized to the middle or inner ear and eighth cranial nerve.

CONCLUSIONS

Children with hypothyroidism have a higher prevalence of hearing loss than children without hypothyroidism. For children with congenital hypothyroidism, evidence of subclinical abnormalities at the level of the cochlea and eighth cranial nerve are present despite early initiation of levothyroxine therapy. Dysfunction of the auditory system might begin with predominance of peripheral conduction abnormalities early in development.

The Role of Anti-Endothelial Cell Autoantibodies and Immune Response in Acute Low-Tone Hearing Loss

OBJECTIVE

Immunity is associated with acute low tone hearing loss. However, the exact pathophysiology of immunity-mediated acute low tone hearing loss remains unknown. In this study, we evaluated the presence, therapeutic effectiveness, and immunopathological mechanisms of anti-endothelial cell autoantibodies (AECEs) in patients with acute low-frequency hearing loss.

MATERIAL AND METHODS

Forty-nine patients who were treated as inpatients having acute low-frequency hearing loss and additional symptoms, such as ear fullness, tinnitus, dizziness, or hyperacusis, were enrolled in this study. Serum samples from these patients were collected for laboratory serum autoimmunity detection, including AECAs, antinuclear antibodies, immunoglobulin, and circular immune complex. Therapeutic responses to combination therapy in short-term outcome and serum cytokine levels were compared between AECA-positive and AECA-negative patients.

RESULTS

Anti-endothelial cell autoantibodies-positive patients tended to show significantly less response to standard therapy compared with AECAs controls (P < .05). Moreover, some serum cytokine levels elevated in both AECAs- and AECAs+ groups. Positive ratio of interleukin-8 and concentrations of macrophage inflammatory protein-1α were found higher in AECAs+ groups (P < .05).

CONCLUSION

The results supported that AECAs might wield influence on the short-term outcome of acute low-tone hearing loss (ALHL) treatment. Furthermore, AECA-mediated acute low-frequency hearing loss possibly involved dysregulation of inflammation process and release of cytokines.

[Immune-mediated sensorineural hearing loss: prevalence and treatment strategies]

Autoimmune sensorineural hearing loss is a rare clinical entity which accounting for less than 1% in all cases with hearing loss. The prevalence of hearing loss in immune-mediated inner ear diseases, as shown in case reports or single-center statistics, varies widely. We reviewed the current literatures on the association between sensorineural hearing loss and autoimmune diseases, focused on the prevalence of hearing loss in different autoimmune diseases, treatments and challenges.

Evaluation of lymphocytic thyroiditis in children with quantitative gray-scale ultrasound echo intensity using a PACS-based tool

PURPOSE

To evaluate diagnostic performance of PACS-based quantitative gray-scale ultrasound as an objective method in evaluation of pediatric thyroiditis.

METHODS

Quantitative measurements of the echo-intensity level of the thyroid were obtained from ultrasound images, retrospectively using a PACS-based tool in 37 children with the tissue-proven diagnosis. Thyroid/muscle ratio was calculated by dividing the mean echo intensity of thyroid by that of adjacent strap muscle. Heterogeneity index (HI) was calculated by dividing thyroid standard deviation (SD) by thyroid mean values. For qualitative evaluation, two radiologists independently reviewed ultrasounds twice for the presence of thyroiditis. A consensus session was performed for patients for whom there was disagreement. Intra- and inter-observer reliability were assessed. Thyroid/muscle ratio and HI were correlated with final pathology.

RESULTS

Lymphocytic thyroiditis was found by histopathology in 19/37 (51%). No significant difference between thyroiditis and normal thyroid groups was found for either thyroid/muscle ratio (1.51 and 1.62, respectively, p = .82) or HI (0.23 and.23, respectively, p = .37). A larger proportion of patients for whom the consensus review indicated thyroiditis were confirmed by histopathology than would be expected by chance alone (12/19 (63%), p = .03). There was fair inter-observer agreement (κ with 95% confidence intervals of 0.36 (0.14-0.57), p = .004) and slight intra-observer agreement for each radiologist (κ with 95% confidence intervals of 0.13 (0.17-0.43), p = .39 and 0.17 (0.15-0.49), p = .31).

CONCLUSION

Quantitative gray-scale echo intensity analysis of US was not sufficient to diagnose thyroiditis in a pediatric population. Consensus qualitative analysis of ultrasound was more consistent with pathological diagnosis.

Hearing loss in autoimmune disorders: Prevalence and therapeutic options

The objective of this study was to review our current knowledge relative to the correlation between sensorineural hearing loss (SNHL) and autoimmune diseases, focusing on the prevalence of hearing loss in different pathologies and possible therapeutic approaches. A review of the literature on hearing loss in different forms of autoimmune disease has been carried out, with emphasis on incidence and prevalence of SNHL. Therapeutic protocols have been assessed including both conservative medical and rehabilitative methods. Cochlear implant outcomes have been investigated. The prevalence of hearing loss in autoimmune and immune-mediated inner ear diseases, as referred by case reports or single-center statistics, is widely variable. More difficult is the evaluation of severe/profound SNHL, usually reported in relation to cochlear implantation. Though these patients represent ideal candidates for cochlear implantation, as they become deaf after years of hearing; the associated systemic disease, the specific damage on inner ear structures and the medication taken may influence the result of cochlear implantation. The main problem is the cochlear fibrosis or ossification that has been found to affect 50% of implanted ears in patients suffering from autoimmune and immune-mediated SNHL. Hence, in the presence of severe/profound SNHL earlier implantation may be indicated before post-inflammatory obliterative changes to the cochlea.

The effect of thyroid autoantibody positivity on the functions of internal ear

The objective of the study is to investigate if any significant difference exists in hearing thresholds and tympanometric examination results among patients whose thyroid antibody positivity was detected approximately 1 year or at least 5 years ago. Study population aged less than 40 years consisted of 17 patients who had thyroid antibody positivities for an average of 1 year (first group), 15 patients who were followed up for at least 5 years for thyroid antibody positivity (second group), and 18 volunteers (third group). Tympanometric examination results, stapes reflex, SRT, SD, and pure tone values were examined. When the second group and the third group were compared, significant results were obtained at hearing frequencies between 500 and 4000 Hz. When the first group and the third group were compared, only at 1000 Hz threshold significant results were obtained. During evaluation of hearing frequencies between 250 and 8000 Hz, significant results were not observed between the second group and the first group. When the first and the second groups were compared with the control group, significant results were obtained as for tympanometric examination findings and significant results were not observed between the second group and the first group. A significant difference was not detected as for the results of stapes reflex. Since thyroid antibody positivity affects the functions of internal ear, these patients should be more closely monitored. Since these effects become deeper in line with increased exposure to autoantibody positivity, variations in auditory responses should be more attentively monitored.