Molecular Biomarkers in Meniere's Disease: A Scoping Review of Current Evidence

OBJECTIVE: Meniere's disease is a complex chronic inner ear condition that is characterized by vertigo, tinnitus, aural fullness, and progressive hearing loss. Currently, diagnostic strategies remain symptom-driven, and treatments focus on management of discrete episodes rather than targeting underlying pathophysiology. This review sets out to evaluate the diagnostic and therapeutic utility of molecular biomarkers derived from blood and endolymphatic fluid in MD. DATA SOURCES: A comprehensive literature search was conducted using OVID Medline, Ovid EMBASE, EBSCO CINAHL, Web of Science Core Collection, ProQuest Dissertations, and the Cochrane Library, utilizing controlled vocabulary (MeSH/Emtree terms) and related keywords. REVIEW METHODS: Following PRISMA guidelines, 2 independent reviewers performed the study screening, data extraction, and bias assessment of the isolated studies. RESULTS: The 21 studies consisted of case-control (71.4%), randomized trials or reviews (14.4%), cohort (9.5%), and case series (4.8%). Isolated biomarkers were classified as structural (24%), regulatory (24%), immunologic/oxidative stress (38%), and miscellaneous (14%). Structural proteins, such as otolin-1, otoconin-90, demonstrated potential in distinguishing MD from other vestibular disorders. Regulatory biomarkers (aquaporin-2, vasopressin-related peptides) were linked to fluid abnormalities. Inflammatory cytokines (TNF-α, IL-6, and IL-1β) and oxidative stress markers (4-HNE) highlighted disease heterogeneity. Additional findings such as unique vitamin D, estradiol, and altered metabolomic profiles suggested hormonal and metabolic changes. CONCLUSION: Molecular biomarkers offer critical insights into MD pathogenesis as well as potential diagnostic and therapeutic advancements. However, methodological variability and lack of replication necessitate standardized validation before formal clinical application.