Table 1.

Mucopolysaccharidoses are classified into several subtypes

Type	Eponym	Enzyme deficiency	GAG	Symptoms
MPSI	Hurler Hurler‐Scheie Scheie	α‐l‐iduronidase	DS/HS	Coarse facial features Short stature +/−Cognitive decline Skeletal abnormalities Hepatosplenomegaly Joint stiffness Cardio‐respiratory disease Recurrent infection
MPSII	Hunter	Iduronate‐2‐sulfatase	DS/HS	Coarse facial features Short stature +/−Cognitive decline Skeletal abnormalities Joint stiffness Hepatosplenomegaly Cardio‐respiratory disease
MPSIII	Sanfilippo A Sanfilippo B Sanfilippo C Sanfilippo D	N‐sulfoglucosamine sulfohydrolase α‐N‐acetylglucosaminidase Heparan‐α‐glucosaminide N‐acetyltransferase N‐acetylglucosamine‐6‐sulfatase	HS	Behavioural problems Cognitive decline Hearing loss
MPSIV	Morquio A Morquio B	Galactosamine‐6‐sulfatase β‐galactosidase	KS/C6‐S KS	Skeletal abnormalities
MPSVI	Maroteaux‐Lamy	N‐acetylgalactosamine 4‐sulfatase	DS	Coarse facial features Joint contractures Hepatosplenomegaly Cardio‐respiratory disease
MPSVII	Sly	β‐glucuronidase	DS/HS/ C4‐,6‐S	Coarse facial features Short stature Cognitive decline Skeletal abnormalities Cardio‐respiratory disease
MPSIX	Natowicz	Hyaluronidase	Hyaluronan	Short stature Frequent ear infections

MPS, mucopolysaccharidosis; DS, dermatan sulphate; HS, heparan sulphate; KS, keratan sulphate; C6‐S, chondroitin 6‐sulphate; C4‐,6‐S, chondroitin 4‐,6‐sulphate; GAS, glycosaminoglycan.