Autoimmune Inner Ear Disease among Patients with Selective IgA Deficiency

Objectives: 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). Materials and Methods: 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 (n approximate to 730,000) with a case-control ratio of 10 controls for each case (1:10). Results: 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%; p = 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%, p = 0.015; sIgAD - AEID group: 76 patients, 21.9%, p < 0.001), with an OR of 8.39 (1.94-36.19; p = 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. Conclusion: The study exposes a significant association between AIED and sIgAD. We believe that sIgAD has to be excluded in AIED patients.