Salla disease, also known as Sialic acid storage disease or infantile free sialic acid storage disorder, is a rare genetic disorder characterized by the abnormal accumulation of a molecule called sialic acid in various tissues and organs of the body. It belongs to a group of disorders known as lysosomal storage disorders, which are caused by defects in lysosomal enzymes that break down various substances.
In individuals with Salla disease, the accumulation of sialic acid occurs due to a mutation in the SLC17A5 gene, which provides instructions for producing a protein called sialin. This protein is responsible for transporting sialic acid out of lysosomes, the cellular compartments involved in the breakdown and recycling of molecules. The defective sialin protein impairs the transportation of sialic acid, leading to its accumulation.
Salla disease is typically diagnosed in infancy, and its symptoms may include developmental delay, intellectual disability, muscle weakness and hypotonia (low muscle tone), seizures, movement disorders, and impaired coordination. Other potential features can include facial dysmorphism (unusual facial appearance), hepatosplenomegaly (enlarged liver and spleen), and skeletal abnormalities.
There is currently no cure for Salla disease, and treatment focuses on managing the symptoms and providing supportive care. This may involve physical, occupational, and speech therapy to address developmental delays, as well as medications to control seizures and movement disorders.
In summary, Salla disease is a rare genetic disorder characterized by the abnormal accumulation of sialic acid due to a mutation in the SLC17A5 gene. It primarily affects infants and leads to developmental and neurological abnormalities.
