[Immunohistochemical detection of humoral autoantibodies in patients with hearing loss in the last hearing ear]

Auditory capacity of the better-hearing ear in asymmetric hearing loss

PURPOSE

Our aim was to investigate the course of the hearing capacity of the better-hearing ear in single-sided deafness (SSD) and asymmetric hearing loss (AHL) over time, in a multicenter study.

METHODS

We included 2086 pure-tone audiograms from 323 patients with SSD and AHL from four hospitals and 156 private practice otorhinolaryngologists. We collected: age, gender, etiology, duration of deafness, treatment with CI, number and monosyllabic speech recognition, numerical rating scale (NRS) of tinnitus intensity, and the tinnitus questionnaire according to Goebel and Hiller. We compared the pure tone audiogram of the better-hearing ear in patients with SSD with age- and gender-controlled hearing thresholds from ISO 7029:2017.

RESULTS

First, individuals with SSD showed a significantly higher hearing threshold from 0.125 to 8 kHz in the better-hearing ear compared to the ISO 7029:2017. The duration of deafness of the poorer-hearing ear showed no relationship with the hearing threshold of the better-hearing ear. The hearing threshold was significantly higher in typically bilaterally presenting etiologies (chronic otitis media, otosclerosis, and congenital hearing loss), except for Menière's disease. Second, subjects that developed AHL did so in 5.19 ± 5.91 years and showed significant reduction in monosyllabic word and number recognition.

CONCLUSIONS

Individuals with SSD show significantly poorer hearing in the better-hearing ear than individuals with NH from the ISO 7029:2017. In clinical practice, we should, therefore, inform our SSD patients that their disease is accompanied by a reduced hearing capacity on the contralateral side, especially in certain etiologies.

[The effect factor and pure threshold average of the ear with normal hearing in patients with single sided deafness]

Objective:To learn the hearing level and analyze the effect factors of hearing loss of the ear with normal hearing in patients with single sided deafness, and provide references for the treatment of single sided deafness. Methods:A retrospective analysis of pure threshold average of 89 patients with single sided deafness, it was divided into six groups,0-6 month group （14 cases）, >6-12 month group （17 cases）, >12-18 month group （15 cases）, >18-24 month group （26 cases）, >24-30 Month group （10 cases）, >30-36 months group （7 cases） in accordance with the different duration of deafness, and compare the pure threshold average of each group; In accordance with the different ages of onset of deafness, it was divided into four groups, 21-30 years old group（18 cases）, >30-40 years old group （24 cases）, >40-50 years old group （30 cases）, >50-60 years old group （17 cases）, and pure threshold average of matching age of normal hearing was compared. Spearman correlation was used to analyze whether gender, side, age of onset of deafness, etiology of deafness, duration of deafness, and pure threshold average hearing were correlated. Results:As the duration of deafness in the affected ear increased, the average pure threshold in patients with single sided deafness increased. As the age of onset of deafness increased, there was a statistically significant difference in age-matched normal hearing. Age of onset of deafness and duration of deafness were the main factors affecting the pure threshold average. Conclusion:In clinical work, the degree of attention to patients with single sided deafness should be increased, hearing of the better hearing ear patients should be protected, and the quality of life will be improved.

Influence of single-sided deafness on the auditory capacity of the better ear

BACKGROUND

Patients with single-sided deafness (SSD) are limited by their asymmetric hearing in various areas of everyday life.

OBJECTIVE

The aim of this investigation was to perform an age-correlated comparison of the hearing threshold of the better ear of SSD patients with a normal-hearing (NH) reference cohort. In addition, the potential influence of etiology, duration of deafness, and cochlear implantation (CI) of the poorer ear on the peripheral hearing ability of the better ear was investigated.

MATERIALS AND METHODS

In a multicenter study, the mean bone conduction hearing threshold of the better ear of 413 adult SSD patients was compared with that of an NH cohort drawn from ISO 7029:2017 for the frequencies 0.5, 1, 2, and 4 kHz.

RESULTS

SSD patients showed significantly poorer hearing in the better ear compared to the age-correlated group of NH subjects. CI, duration of deafness, and etiology had no significant effect on the hearing ability of the better ear.

CONCLUSION

The origin of the poorer hearing of the better-hearing ear of SSD patients compared to an age-correlated NH cohort is still unclear. It is most likely a combination of different anatomical, immunological, etiological, and microcirculatory causes, which lead to poorer hearing of the better-hearing ear in SSD patients.

Autoimmune-Mediated Sympathetic Hearing Loss: A Case Report

BACKGROUND

Damage to one inner ear is occasionally followed by contralateral sensorineural hearing loss. This has been defined as sympathetic hearing loss.

HYPOTHESIS

It is hypothesized that autoimmunity can play a role in the pathogenesis of sympathetic hearing loss.

METHODS

A male patient who developed right-sided sympathetic hearing loss at 20 years of age, 11 years after deafness of the left ear caused by a temporal bone fracture, is described. The patient's serum was analyzed for the presence of autoantibodies against inner ear tissues by immunocytochemistry and Western blotting using rat inner ear tissues. The patient's serum was tested specifically for antibodies against heat shock protein 70 by immunodot blot. The presence of autoantibodies known to play a role in systemic autoimmune disease was also examined.

RESULTS

Immunocytochemistry on rat temporal bone sections demonstrated autoantibodies in the patient's serum specifically targeted against cochlear outer hair cells. No reactivity of the patient's serum was observed with control tissues including kidney, brain, and liver. Western blotting using homogenized rat cochlear tissues showed that the patient's serum reacted with a 25- and 27-kDa protein. No reactivity was observed with heat shock protein 70 in the immunodot blot analysis. The patient's serum did not contain autoantibodies against antinuclear antibodies, double-stranded DNA, antineutrophil cytoplasmic antibodies, basement membrane, reticulin, intestinal mucosa, muscle, collagen, or mitochondria.

CONCLUSION

Observations indicate that this patient suffered sympathetic hearing loss caused by organospecific autoimmunity directed to cochlear outer hair cells.

Autoimmune inner ear disorders

There is considerable evidence to suggest that hearing and vestibular function can be influenced by autoimmune processes. A number of systemic autoimmune disorders include hearing loss and vertigo as part of their constellation of symptoms. Although classic evidence for a specific autoimmune etiology mediated by immune response directed solely at the inner ear is elusive, it appears that autoimmune damage can also exist as an entity confined to the labyrinth. Antigenic targets of autoimmunity within the labyrinth seem to be diverse. Partly because of this, the condition is difficult to diagnose. However, autoimmune disorders of the inner ear are of special interest since they are among the few forms of hearing loss that are amenable to medical treatment. Recent progress in understanding the etiology, diagnosis and treatment of autoimmune damage to the inner ear is reviewed.