Kearns-Sayre Syndrome

What is Kearns-Sayre Syndrome (KSS)?

Kearns-Sayre syndrome is a condition that affects many parts of the body, especially the eyes. The features of Kearns-Sayre syndrome usually appear before age 20, and the condition is diagnosed by a few characteristic signs and symptoms.

At least one of the following must also be present: cardiac conduction block, cerebrospinal fluid protein concentration greater than 100 mg/dL, or cerebellar ataxia.

What are the symptoms of Kearns-Sayre Syndrome (KSS)?

At least one of the following must also be present: cardiac conduction block, cerebrospinal fluid protein concentration greater than 100 mg/dL, or cerebellar ataxia.

Other symptoms include:

Mild skeletal muscle weakness
Short stature
Hearing loss
Impaired cognitive function
Diabetes mellitus
Infrequent seizures

Furthermore, several endocrine disorders can be associated with Kearns-Sayre syndrome, including delayed sexual maturation, hypothyroidism, and growth hormone deficiency.

What causes Kearns-Sayre Syndrome (KSS)?

Kearns-Sayre syndrome is caused by defects in mitochondria, which are structures within cells that use oxygen to convert the energy from food into a form that can be used by cells.

People with Kearns-Sayre syndrome have a single, large deletion of mtDNA which results in the loss of genes important for mitochondrial formation. While researchers have not determined how these deletions cause the features of Kearns-Sayre syndrome, they may be related to a lack of cellular energy The underlying cause of the deletion in affected individuals remains unknown.

How is Kearns-Sayre Syndrome (KSS) diagnosed?

The diagnosis of KSS may be suspected when the three primary characteristics associated with this disorder occur in association with one another. These include:

Paralysis of certain eye muscles (chronic progressive external ophthalmoplegia, or CPEO)
Abnormal coloration of the delicate membrane lining the eyes (atypical retinitis pigmentosa)
Other changes in the structures of the eye (pigmentary degeneration of the retina)

Diagnosis of KSS may be confirmed by a thorough clinical evaluation and a variety of specialized tests.

What are the treatments for Kearns-Sayre Syndrome (KSS)?

Treatment for Kearns-Sayre syndrome is generally symptomatic and supportive.

Management options include:

Placement of cardiac pacemakers in individuals with cardiac conduction blocks
Eyelid slings for severe ptosis
Cochlear implants and hearing aids for neurosensory hearing loss
Hormone replacement for endocrinopathies
Dilation of the upper esophageal sphincter to alleviate cricopharyngeal achalasia

Where can I find out more about Kearns-Sayre Syndrome (KSS)?