Lysosomal Transport Defects
Disease (OMIM Number) | Defective Proteins or Enzymes | Comments |
|---|---|---|
Sialuria | ||
Infantile sialic acid storage disorder (269920*) | Sodium phosphate cotransporter | Onset: At birth Urine metabolites: Increased free sialic acid Clinical features: Growth failure, coarse facial features, dysostosis multiplex, nystagmus, ptosis, gingival hypertrophy, cardiomegaly, heart failure, hepatosplenomegaly, nephrosis, death at about age 1 year Treatment: Supportive care |
Finnish type (Salla disease; 604369*) | Sodium phosphate cotransporter | Onset: 6–9 months Urine metabolites: Increased free sialic acid Clinical features: Growth failure, developmental disability, ataxia, hypotonia, hypotonia, spasticity, dyspraxia, dysarthria, seizures, gait problems, athetosis; increased frequency in Finland Treatment: Supportive care |
French type (269921*) | UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase | Onset: Infancy to early childhood Urine metabolites: Increased free sialic acid Clinical features: Coarse facies with normal growth, developmental delay, sleep apnea, hypoplastic nipples, hepatosplenomegaly, inguinal hernias, generalized hirsutism, seizures Treatment: Supportive care |
Neuronal ceroid lipofuscinosis (CLN3, CLN5, CLN6, CLN8) | See table Other Lipidoses | — |
Cystinosis | Cystinosin (lysosomal cystine transporter) | |
Infantile nephropathic form (219800*) | Onset: First year Urine metabolites: Renal Fanconi syndrome Clinical features: Growth failure, frontal bossing, photophobia, peripheral retinopathy with decreased acuity, corneal crystals and erosion, rickets, hepatosplenomegaly, pancreatic insufficiency, renal calculi, renal failure, renal Fanconi syndrome, decreased sweating, myopathy, dysphagia, cerebral atrophy, normal intelligence but neurologic deterioration in long-term survivors Cystine accumulation throughout reticuloendothelial system, white blood cells, and corneas Treatment: | |
Late-onset juvenile or adolescent form (219900*) | Onset: 12–15 years Urine metabolites: Renal Fanconi syndrome Clinical features: Similar to infantile form but milder Treatment: Similar to that for infantile form | |
Adult non-nephropathic form (219750*) | Onset: Early adolescence to adulthood Urine metabolites: Renal Fanconi syndrome Clinical features: Similar to infantile form but no renal disorders Treatment: | |
* For complete gene, molecular, and chromosomal location information, see the Online Mendelian Inheritance in Man (OMIM) database. | ||