Establishing a core outcome set for mucopolysaccharidoses (MPS) in children: study protocol for a rapid literature review, candidate outcomes survey, and Delphi surveys

Table 1 Summary of MPS subtypes

MPS subtype	Common name(s)	Enzyme deficiency^c	Neuronopathic involvement^d
I
IH^a,b	Hurler syndrome	α-L-iduronidase	+
IA^a	Attenuated MPSI, Hurler-Scheie syndrome, Scheie syndrome	α-L-iduronidase	+/-
II
IIA^a	Hunter (severe) syndrome	Iduronate sulfatase	+
IIB^a	Hunter (mild) syndrome	Iduronate sulfatase	+/-
III
IIIA	Sanfilippo syndrome A	Heparan N-sulfatase	+
IIIB	Sanfilippo syndrome B	α-N-acetyl-glucosaminidase	+
IIIC	Sanfilippo syndrome C	Acetyl CoA:α glucosaminide acetlytransferase	+
IIID	Sanfilippo syndrome D	N-acetylglucosamine 6-sulfatase	+
IV
IVA^a	Morquio syndrome A	N-acetylgalactosamine 6-sulfatase (GALNS)	-
IVB	Morquio syndrome B	β-galactosidase	+/-
VI^a	Maroteaux-Lamy syndrome	N-acetylgalactosamine 4-sulfatase (Arylsulfatase B)	-
VII^a,b	Sly syndrome	β-glucuronidase	+
IX	Natowicz syndrome	Hyaluronidase	-

MPS mucopolysaccharidosis
^aEnzyme replacement therapy (ERT) is frequently used for this subtype of MPS
^bHematopoietic stem cell transplantation (HSCT) is used for this subtype of MPS
^cInformation taken from Zhou and colleagues 2020 [23]
^d+ Typical for this subtype, −atypical for this subtype, and +/− occurs in some cases or depends on how neuronopathic involvement is defined

ISSN: 1745-6215