Sialic acid accumulated in the cell is stored as free sialic acid as observed in Salla disease and infantile sialic acid storage disease
or accumulates as bound to other glycopeptides or oligosaccharides as observed in sialidosis.
Sialic acid storage diseases (SSDs) (3) are autosomal recessive neurodegenerative disorders that may present as a severe infantile form, infantile sialic acid storage disease (ISSD), or as a slowly progressive adult form that is prevalent in the Finnish population, called Salla disease (1).
Sialic acid storage disease of the Salla phenotype in American monozygous twin female sibs.
(3) Nonstandard abbreviations: SSD, sialic acid storage disease; ISSD, infantile sialic acid storage disease; NANA, N-acetylneuraminic acid (free sialic acid); HPAE-PAD, high-performance anion-exchange pulsed amperometric detection; tMS, tandem mass spectrometry; KDN, 2-keto-3-deoxy-D-glycero-D-galactonononic acid; IS, internal standard; ESI, electrospray ionization; MRM, multiple reaction monitoring; ERNDIM, European Research Network for Evaluation and Improvement of Screening Diagnosis and Treatment of Inherited Disorders of Metabolism; and LOD, limit(s) of detection.
Proton nuclear magnetic resonance spectroscopic detection of sialic acid storage disease
. Clin Chem 2002;48:357-9.
Sialic acid storage disease (SASD) is a rare autosomal recessive lysosomal storage disorder characterized by excessive urinary excretion of free sialic acid and an accumulation of free sialic acid in skin fibroblasts (1).
Sialic acid storage disease with sialuria: clinical and biochemical features in the severe infantile type.
Defective lysosomal egress of free sialic acid (N-acetylneuraminic acid) in fibroblasts of patients with infantile free sialic acid storage disease. J Biol Chem 1989;264:15316-22.
(d) GM I, GM I gangliosidosis; MLD, metachromatic leukodystrophy; MSD, multiple sulfatase deficiency; MPS, mucopolysaccharidosis; N-P, Niemann-Pick disease; SAS, sialic acid storage disease
; TSD, Tay-Sachs disease.