Kearns-Sayre Syndrome

Kearns-Sayre syndrome (KSS) is a neuromuscular disorder defined by the triad of onset before age 20 years, pigmentary retinopathy (a "salt-and-pepper" pigmentation in the retina that can affect vision, but often leaves it intact), and progressive external ophthalmoplegia (PEO). In addition, affected individuals have at least one of the following: cardiac conduction block, cerebrospinal fluid protein concentration greater than 100 mg/dL, or cerebellar ataxia. Kearns-Sayre syndrome is a mitochondrial DNA (mtDNA) deletion syndrome. It results from abnormalities in the DNA of mitochondria - small rod-like structures found in every cell of the body that produce the energy that drives cellular functions. This and other mitochondrial diseases correlate with specific DNA mutations that cause problems with many of the organs and tissues in the body, resulting in multisystem effects. Treatment for this slowly progressive disorder is generally symptomatic and supportive.