Kearns Sayre Shy Daroff Syndrome (KSSD) is a rare and progressive disorder that primarily affects the muscles involved in eye movement and coordination. It is named after the three physicians who first described its characteristics in 1965: Brian B. Kearns, George P. Sayre, and Richard G. Shy.
KSSD is classified as a mitochondrial disorder, meaning that it is caused by abnormalities in the DNA of the mitochondria, the structures within cells responsible for generating energy. The primary symptom of KSSD is the presence of one or more of the following: progressive external ophthalmoplegia (PEO), which is characterized by the weakness or paralysis of the muscles that control eye movement; pigmentary retinopathy, a condition that causes changes in the pigmented layer of the retina, leading to visual impairment; and degenerative cerebellar ataxia, which results in impaired coordination, balance, and voluntary muscle control.
The onset of symptoms in KSSD can vary widely, but they typically appear in childhood or adolescence. Other signs and symptoms may include muscle weakness in the limbs, hearing loss, heart block, short stature, and endocrine abnormalities. KSSD is a multisystem disorder, meaning it can affect multiple parts of the body in addition to the eyes and muscles.
Currently, there is no cure for KSSD, and treatment primarily focuses on managing symptoms and improving quality of life. This may include the use of eyeglasses, hearing aids, physical therapy, and other supportive measures tailored to each individual's needs. Due to its progressive nature, individuals with KSSD often require ongoing medical care and monitoring to address complications that may arise.
