Autosomal recessive neurodegenerative disorders caused by lysosomal membrane transport defects that result in accumulation of free sialic acid (N-ACETYLNEURAMINIC ACID) within the lysosomes. The two main clinical phenotypes, which are allelic variants of the SLC17A5 gene, are ISSD, a severe infantile form, or Salla disease, a slowly progressive adult form, named for the geographic area in Finland where the kindred first studied resided.

Synonyms: Sialurias, Infantile Form Sialic Acid Storage Disease, Finnish Type Salla Disease Sialurias Finnish Type Sialuria Infantile Sialic Acid Storage Disorder Sialuria Sialuria, Infantile Form Infantile Form Sialurias Finnish Type Sialurias French Type Sialuria Infantile Sialic Acid Storage Disorder (ISSD) Sialic Acid Storage Disease Sialurias, Finnish Type Sialic Acid Storage Disease, Infantile Form Sialuria, Finnish Type Infantile Form Sialuria Infantile Sialic Acid Storage Disease