Kearns-Sayre syndrome is a mitochondrial disorder characterised by progressive external ophthalmoplegia, pigmentary retinopathy, and systemic involvement. Onset is usually before age 20.
Ocular features
Eye signs are often the first clue.
- Bilateral ptosis and limited eye movements with preserved pupil responses
- Atypical salt-and-pepper pigmentary retinopathy
- Gradual reduction in visual acuity and night vision
- Due to large-scale mitochondrial DNA deletions
Systemic issues and management
Patients require careful cardiac and systemic surveillance.
- Risk of heart block, ataxia, and endocrine abnormalities
- Pacemaker insertion may be lifesaving in conduction disease
- Ptosis surgery and prisms can improve visual function
- Genetic counselling and family assessment for mitochondrial disease