raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:309294

Sialidosis

Type
Clinical group
Group
Group of disorders
Inheritance
Autosomal recessive
Age of onset
All ages
Status
active

Sialidosis is a lysosomal storage disease, belonging to the group of oligosaccharidoses or glycoproteinoses, with a wide clinical spectrum that is divided into two main clinical subtypes: sialidosis type I, the milder, non dysmorphic form of the disease characterized by gait abnormalities, progressive visual loss, bilateral macular cherry red spots and myoclonus, that presents in adolescence or adulthood (second or third decade of life); and sialidosis type II the more severe, early onset form, characterized by a progressive and severe mucopolysaccharidosis-like phenotype with coarse facies, visceromegaly, dysostosis multiplex, and developmental delay. Bilateral macular cherry red spots are also present. Sialidosis type II has been further divided into congenital (with hydrops fetalis), infantile and juvenile presentations.

1

Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enSialidosis
frSialidose
deSialidose
esSialidosis
itSialidosi
nlSialidose
ptSialidose
plSialidoza
csSialidóza
ukСіалідоз
zh唾液酸沉积病
trSiyalidoz

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
ICD-115C56.21NTBTindexvalidated
MONDO0017734Evalidated
MONDO17734Evalidated
UMLSC0268226Evalidated
MedDRA10058800Evalidated

E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.

3

Classification

Preferential parent (Orphanet linearisation):

Parents in the classifications (2):

Children (2):

4

Genes

0 direct

Orphanet records no gene directly on this code.

5

Prevalence and incidence

6 records
TypeClassValueAreaQualificationValidationSource
Prevalence at birth1-9 / 1 000 0000.1 / 100 000SwedenValue and classValidated25274184[PMID]
Prevalence at birth<1 / 1 000 0000.05 / 100 000EuropeValue and classValidated10480370[PMID]
Prevalence at birth<1 / 1 000 0000.07 / 100 000Czech RepublicValue and classValidated20490927[PMID]
Prevalence at birth<1 / 1 000 0000.05 / 100 000NetherlandsValue and classValidated10480370[PMID]
Prevalence at birth<1 / 1 000 0000.02 / 100 000AustraliaValue and classValidated9918480[PMID]
Point prevalence<1 / 1 000 000—EuropeClass onlyValidatedORPHANET

Value is Orphadata's ValMoy: the mean estimate per 100 000 for prevalence and incidence, the number of cases or families for case reports.

6

HPO phenotypes

Orphanet has no HPO annotation for this code in this release.

7

Sources for this card