Sjögren-Larsson syndrome

Sjögren-Larsson syndrome is a condition that affects the skin and eyes as well as the brain and spinal cord (central nervous system). 

Infants with Sjögren-Larsson syndrome tend to be born prematurely. At birth, the skin may be thicker than normal (hyperkeratosis) and red (erythema), but it typically becomes dry and scaly (ichthyosis). Mild to severe itchiness (pruritus) is also common. The skin abnormalities generally affect the neck, torso, arms, and legs. The face is usually not affected.

Tiny crystals in the light-sensitive tissue at the back of the eye (retina) can be seen during an eye exam in most affected individuals who are older than 3 to 4 years of age. This feature is unique to people with Sjögren-Larsson syndrome and can be used to diagnose the condition. These retinal crystals are often called “glistening white dots.” People with Sjögren-Larsson syndrome may also have nearsightedness (myopia) or an increased sensitivity to light (photophobia).

People with Sjögren-Larsson syndrome may have neurological signs and symptoms. Affected individuals often have leukoencephalopathy, which is a change in a type of brain tissue called white matter. White matter consists of nerve fibers that are covered by a substance (myelin) that insulates and protects the nerves. Leukoencephalopathy is thought to contribute to many of the neurological signs and symptoms seen in people with Sjögren-Larsson syndrome.

Most people with Sjögren-Larsson syndrome have intellectual disabilities, which can vary from mild to severe. Speech difficulties (dysarthria) are common, and speech development is often delayed. Affected individuals typically have more trouble speaking than understanding language. Approximately 35 to 40 percent of people with Sjögren-Larsson syndrome have seizures.

Children with Sjögren-Larsson syndrome typically experience abnormal muscle stiffness (spasticity) in their legs and, less commonly, in their arms. The spasticity may cause a delay in the development of motor skills such as sitting, crawling, and walking. Joint deformities (contractures) are also common. Approximately 50 percent of people with Sjögren-Larsson syndrome will require wheelchair assistance.