disease overview

Not all people with Hunter syndrome are affected by the disease in exactly the same way; the type and severity of symptoms, age that symptoms appear, and the rate of symptom progression all vary widely.

Non-neuropathic

NON-NEUROPATHIC (ATTENUATED) MPS II

  • Physical symptoms are milder
  • Disease progression is slower
  • Cognitive development is not affected
Brain

Developmental
delays

ABC building blocks

Speech
delays

Ear infections Hearing loss

Ear infections
Hearing loss

Cardiovascular complications

Cardiovascular
complications

Enlarged liver and spleen

Enlarged liver
and spleen

Respiratory problems

Respiratory
problems

Joint stiffness

Joint
stiffness

Curled fingers

Curled
fingers

Non-neuropathic

NEUROPATHIC (SEVERE) MPS II

  • Developmental and speech delays
  • Disease progression is faster
  • Life expectancy is shorter

Non-neuropathic

Neuropathic

Hunter syndrome was traditionally categorized into two distinct types, severe and attenuated (now often labeled neuropathic and non-neuropathic), based on the degree of cognitive impairment involved. The severe type was defined by the presence of neurological symptoms alongside physical symptoms, all of which generally become apparent between 2 and 4 years of age. For the attenuated type, minimal cognitive impairment is involved and symptoms may only present in late childhood or early adolescence. However, due to the highly variable nature of Hunter syndrome and variety of presentation between these two types, Hunter syndrome can now be better understood as a spectrum of severity.