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.