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Hyaluronidase deficiency

Disease definition

A rare form of mucopolysaccharidosis characterized by abnormal storage of hyaluronan in lysosomes due to deficiency of hyaluronidase 1. Clinical manifestations include knee and/or hip pain associated with swelling, diffuse joint involvement with proliferative synovitis and occurrence of multiple periarticular soft-tissue masses, short stature, and dysmorphic craniofacial features (such as flattened nasal bridge, bifid uvula, and cleft palate).


Classification level: Disorder
  • Synonym(s):
    • MPS9
    • MPSIX
    • Mucopolysaccharidosis type 9
    • Mucopolysaccharidosis type IX
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Childhood
  • ICD-10: E76.2
  • ICD-11: 5C56.3Y
  • OMIM: 601492
  • UMLS: C1291490
  • MeSH: C563209
  • GARD: -
  • MedDRA: -

Detailed information

General public


Clinical Outcome Assessment (COA)

  • Patient-Centered Outcome Measures (PCOMs)
  • English (2023) - PROQOLIDTM
ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.