Hearing Involvement in Active ANCA-Associated Vasculitis: The Role of High-Frequency Audiometry in Early Detection

Objectives: Ear involvement is a common feature of antineutrophil antibody (ANCA)-associated vasculitis (AAV). The vigilance of otolaryngologists often determines early diagnosis of AAV, thereby reducing the risk of irreversible organ damage and improving the quality of life of these patients. The goal of this study was to assess the quantitative and qualitative hearing impairment in patients with active AAV and to identify an audiological test that can detect of early deterioration of hearing even in patients without hearing loss. Methods: A study group of 46 patients with ANCA-associated vasculitis (AAV) hospitalized at the Department of Internal Diseases, Nephrology and Dialysis, Military Institute of Medicine-National Research Institute and a control group of 20 patients without a diagnosis of ANCA vasculitis and with no reported hearing disturbances were assessed prospectively. A battery of audiologic tests were carried out including High Frequency Audiometry, Impedance Audiometry, Otoacoustic Emissions, and Auditory Brainstem Responces (ABR). Computed Tomography of temporal bones and paranasal sinuses were performed, and audiologic anamnesis was gathered. Results: Pure-tone audiometry (PTA) demonstrated hearing loss in 58.6% (51/87) of the ears in the study group. The predominant type of damage was sensorineural hearing loss (SNHL). No correlation was found between hearing loss and AAV activity, duration of the disease, number of relapses, or ANCA antibody type. The statistically significant differences between control group and study group, even after excluding patients with hearing loss, were observed for high frequency audiometry (p < 0.001, for all tested frequencies excluding 14,000 Hz). The otoacoustic emissions showed to be statistically insignificant after exclusion of patients with hearing loss. Conclusions: Hearing involvement is common in patients with AAV regardless of the type of ANCA antibodies. High Frequency Audiometry could be an important audiologic screening test in this group of patients, and should be incorporated to diagnostic test battery in AAV. Otoacoustic emissions and ABR can be a handful in uncertain cases.