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The Role of Primary Mitochondrial Disorders in Hearing Impairment: An Overview

Virginia Fancello1, Giuseppe Fancello2, Silvia Palma3

  • 1ENT & Audiology Unit, Department of Neurosciences, University Hospital of Ferrara, 44124 Ferrara, Italy.

Medicina (Kaunas, Lithuania)
|March 29, 2023
PubMed

Insights

Primary mitochondrial diseases (PMDs) can cause hearing loss in 40.8% of patients. This sensorineural hearing impairment is often bilateral and progressive, signaling potential systemic issues.

Area of Science:

  • Genetics
  • Neurology
  • Ophthalmology
  • Endocrinology

Background:

  • Primary mitochondrial diseases (PMDs) stem from mitochondrial DNA (mtDNA) defects affecting the electron transport chain.
  • These conditions present diverse phenotypes, often including hearing impairment, impacting clinical diagnosis.
  • Understanding the link between PMDs and hearing loss is crucial for comprehensive patient care.

Approach:

  • A systematic review followed PRISMA guidelines, searching Medline up to December 2022.
  • Seven relevant studies, identified from 485 initial papers, were included in this analysis.
  • Data from 759 patients with PMDs and hearing loss were synthesized.

Key Points:

  • Hearing loss affects 40.8% of patients with PMDs (310/759).
  • The hearing impairment is predominantly sensorineural, bilateral, symmetrical, and progressive.
  • Patient age ranged from 2 days to 78 years, with a 1.3:1 male-to-female ratio.

Conclusions:

  • PMDs are complex disorders with varied clinical presentations.
  • Bilateral, progressive hearing loss in PMD patients may indicate underlying systemic involvement.
  • Genetic testing is essential for diagnosing PMDs and associated hearing loss.
Keywords:
geneticsmetabolic disordersmitochondrial diseasessensorineural hearing loss

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