A rare inherited biochemical disorder characterized by the accumulation of mucopolysaccharides (glycosaminoglycans) in various body tissues due to insufficient amounts of the enzyme (?-L-diuronidase) needed to break it down. There are three main sub-types of the disorder: Hurler - severe form, Scheie - mild form and Hurler/Scheie form which is intermediate. See also Mucopolysaccharidosis type I Hurler syndrome