Recurrent Benign Paroxysmal Positional Vertigo in DFNB16 Patients with Biallelic STRC Gene Deletions

Abstract

Objective Deletions of STRC gene (DFNB16) account for 12% of isolated congenital mild to moderate hearing loss (HL). In mice, the stereocilin protein, encoded by STRC, is present in the vestibular kinocilium embedded in the otoconial membrane of the utricular macula. Despite this, effects on vestibular function have not been widely investigated. The aim of this study was to investigate the prevalence of benign paroxysmal positional vertigo (BPPV) in a cohort of DFNB16 patients. Study Design Observational descriptive epidemiological study. Setting Single-center study, in a tertiary referral center. Patients Older than 5 years, with a genetic diagnosis of HL related to biallelic STRC gene deletions, diagnosed between 2015 and 2021 Intervention Patients or their parents were interviewed to determine whether they had experienced vertigo or episodes of BPPV. Main Outcome Measure Criteria were at least five acute episodes of rotatory vertigo, each lasting less than 1 minute, episodes triggered by changes in specific head position, and an absence of neurological symptoms. Results Sixty-four patients having mild (33%) to moderate (66%) HL were included. Median age was 15 years (range, 6–48 yr). Prevalence of BPPV was 39% (25 of 64). Median age of first onset was 13 years (range, 3–18 yr). Conclusions This study showed recurrent BPPV and early age of onset in patients with biallelic STRC gene deletions. BPPV may be associated with the HL phenotype in patients with STRC gene deletions. It is important to inform patients and families of this potential risk such that appropriate management can be proposed.