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Updated: May 28, 2026
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Behavioral Assessment of Hearing in 2 to 4 Year-old Children: A Two-interval, Observer-based Procedure Using Conditioned Play-based Responses
Published on: January 23, 2017
Hearing loss in children with mitochondrial disorders
Sri Kiran Chennupati1, Jessica Levi, Patricia Loftus
1St. Christopher's Hospital for Children, Division of Otolaryngology, 3601 A Street, Philadelphia, PA 19134, United States.
International Journal of Pediatric Otorhinolaryngology
|October 11, 2011
Summary
Mitochondrial disorders in children can cause hearing loss, but it
Area of Science:
- Pediatrics
- Genetics
- Audiology
Background:
- Congenital hearing loss affects 1-5 per 1000 children, with 50% genetic causes.
- Mitochondrial DNA mutations account for an estimated 1% of pre-lingual hearing loss.
- Previous studies on hearing loss in mitochondrial disorders involved small patient cohorts (typically <20).
Purpose of the Study:
- To characterize hearing loss in children with mitochondrial mutations.
- To determine if previously reported patterns (progressive, sensorineural, high-frequency loss) are present in this patient population.
Main Methods:
- Retrospective chart review of electronic medical records (2004-2009).
- Identified 149 patients with mitochondrial disorders using ICD-9 codes.
- Analyzed audiologic data from 26 patients with both mitochondrial disorders and hearing evaluations.
Main Results:
- 15 out of 26 patients (58%) exhibited hearing loss.
- Sensorineural hearing loss was most common (38%), followed by conductive (7.7%) and mixed (3.8%) types.
- Hearing loss patterns were variable, including low and mid-frequency losses, and were not always progressive.
Conclusions:
- This study provides one of the largest audiometric datasets for children with mitochondrial disorders.
- Hearing loss in this cohort was more diverse than previously reported, including non-progressive and variable frequency losses.
- Routine audiometric screening, including ABR and OAEs, is recommended for children with mitochondrial disorders to detect potential hearing impairments and monitor progression.
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