A lysosomal storage disease with multisystemic involvement leading to a massive accumulation of glycosaminoglycans and a wide variety of symptoms including distinctive coarse facial features, short stature, cardio-respiratory involvement and skeletal abnormalities. It manifests as a continuum varying from a severe form with neurodegeneration to an attenuated form without neuronal involvement.

A condition characterized by obstruction of the airway and by pauses in breathing during sleep occurring many times during the night. Obstructive sleep apnea is related to a relaxation of muscle tone (which normally occurs during sleep) leading to partial collapse of the soft tissues in the airway with resultant obstruction of the air flow.