Clinical Characteristics of Patients With Dizziness/Vertigo Accompanied by Posterior Semicircular Canal Hypofunction

Objective: To investigate the clinical characteristics of patients with dizziness/vertigo accompanied by loss of the posterior canal(s) (LPC).Methods: Clinical data of 23 patients with LPC were collected. We determined video-head-impulse test (vHIT) gains of all six semicircular canals and correlated vHIT findings with other vestibulo-cochlear tests, including caloric test, ocular and cervical vestibular-evoked myogenic potentials (oVEMP, cVEMP), pure tone audiometry (PTA), and analyzed the differences in clinical manifestations of patients with LPC with different etiologies.Results: LPC was identified in 23 patients. At the time of disease onset, most patients presented with dizziness (47.8%) and vertigo (30.4%) only, and some patients (21.7%) complained of unsteadiness. Among these 23 patients with LPC, there were 14 (60.9%) patients of isolated LPC (ILPC), 21 (91.3%) patients of unilateral LPC (ULPC), and 2 (8.7%) patients of bilateral LPC (BLPC). (1) Among 14 patients with ILPC, 13 (92.9%) patients had unilateral ILPC, the rate of ipsilesional impairment on caloric test, or oVEMP/cVEMP test or PTA ipsilesionally was 53.8% (7/13) in patients with unilateral ILPC. The causes of unilateral ILPC were vertigo/dizziness of unclear origin (38.5%), labyrinthine infarction (15.4%), vestibular migraine (15.4%), and other diseases (30.8%); (2) among 21 patients with ULPC, 7 patients (33.3%) were accompanied with horizontal semicircular canal hypofunction ipsilesionally, the abnormal rate of caloric test, or oVEMP/cVEMP tests or PTA ipsilesionally was 57.1%. The causes of ULPC were vertigo/dizziness of unclear origin (33.3%), autoimmune inner ear disease (14.3%), labyrinthine infarction (14.3%), vestibular neuritis (9.5%), vestibular migraine (9.5%), and other diseases (19.0%); (3) among two patients with BLPC, one patient presented with unsteadiness, the causes of BLPC were vestibular paroxysmia and autoimmune inner ear disease.Conclusion: vHIT is a fast and effective method for assessing LPC, which can be used to detect isolated PC dysfunction. The causes of ILPC were peripheral origin or central origin. Patients with ILPC and ULPC mostly presented with dizziness/vertigo, and ULPC was often accompanied by ipsilateral vestibulo-cochlear impairment.

Autoimmune Inner Ear Disease among Patients with Selective IgA Deficiency

<b><i>Objectives:</i></b> Autoimmune inner ear disease (AIED) is a distinct clinical entity from sudden sensorineural hearing loss. The purpose of this study was to investigate the clinical characteristics of AIED in patients with selective IgA deficiency (sIgAD). <b><i>Materials and Methods:</i></b> This retrospective observational study was based on data from the Leumit Healthcare Services database in Israel. We searched all subjects aged ≥12 years who had undergone serum total IgA measurements during 2004–2014 for any reason. The sIgAD patients included all subjects with serum IgA of ≤7 mg/dL (0.07 g/L). A control group was randomly sampled from the full study population (<i>n</i> ≈ 730,000) with a case-control ratio of 10 controls for each case (1:10). <b><i>Results:</i></b> Among 347 subjects with sIgAD, we identified 9 patients with concomitant AIED (sIgAD + AIED group). This group was characterized by a higher prevalence of allergic diseases (8 patients; 88.9%) than sIgAD patients without AEID (sIgAD + AIED group; 153 patients; 45.2%; <i>p</i> = 0.014). Both systemic diseases (3 patients; 33.3%) and organ-specific autoimmune diseases (7 patients; 77.8%) were more prevalent in the sIgAD + AIED group (sIgAD + AIED group: 19 patients 5.5%, <i>p</i> = 0.015; sIgAD − AEID group: 76 patients, 21.9%, <i>p</i> &#x3c; 0.001), with an OR of 8.39 (1.94–36.19; <i>p</i> = 0.004). sIgAD patients with and without AIED were characterized by a higher prevalence of documented episodes of acute otitis media, allergic diseases, and autoimmune diseases than the control group. <b><i>Conclusion:</i></b> The study exposes a significant association between AIED and sIgAD. We believe that sIgAD has to be excluded in AIED patients.

Unilateral autoimmune inner ear disease in a patient with lung cancer treated with nivolumab

ABSTRACT A 69-year-old male presented with early stage non-small cell lung cancer in 2016. The tumor was resected; however, the patient experienced recurrence 2 years later and subsequently received paclitaxel/carboplatin concurrently with radiotherapy. Within weeks of completing this treatment, he developed a symptomatic pancoast tumor secondary to disease progression and commenced second line nivolumab. Following the second dose of nivolumab, he developed acute unilateral right hearing loss. He commenced intravenous methylprednisolone followed by a slow taper of oral prednisolone. With steroids, he noted a gradual improvement in hearing, confirmed by audiology. Restaging imaging post-nivolumab demonstrated a complete metabolic response. Two prior cases have reported bilateral sensorineural hearing loss post-immune checkpoint inhibitor (ICI). We postulate the hearing impairment relates to the development of autoimmune inner ear disease. To our knowledge, this is the only case of a patient experiencing unilateral loss of hearing following an ICI.