title: Diagnosis and treatment trends in mucopolysaccharidosis I: findings from the MPS I Registry.
abstract: Our objective was to assess how the diagnosis and treatment of mucopolysaccharidosis I (MPS I) have changed over time. We used data from 891 patients in the MPS I Registry, an international observational database, to analyze ages at symptom onset, diagnosis, treatment initiation, and treatment allocation (hematopoietic stem cell transplantation, enzyme replacement therapy with laronidase, both, or neither) over time for all disease phenotypes (Hurler, Hurler-Scheie, and Scheie syndromes). The interval between diagnosis and treatment has become shorter since laronidase became available in 2003 (gap during 2006-2009: Hurler--0.2 year, Hurler-Scheie--0.5 year, Scheie--1.4 years). However, the age at diagnosis has not decreased for any MPS I phenotype over time, and the interval between symptom onset and treatment initiation remains substantial for both Hurler-Scheie and Scheie patients (gap during 2006-2009, 2.42 and 6.71 years, respectively). Among transplanted patients, an increasing proportion received hematopoietic stem cells from cord blood (34 out of 64 patients by 2009) and was also treated with laronidase (42 out of 45 patients by 2009).
  
  
  CONCLUSIONS
  Despite the availability of laronidase since 2003, the diagnosis of MPS I is still substantially delayed for patients with Hurler-Scheie and Scheie phenotypes, which can lead to a sub-optimal treatment outcome. Increased awareness of MPS I signs and symptoms by primary care providers and pediatric subspecialists is crucial to initiate early treatment and to improve the quality of life of MPS I patients.
authors.affiliation: Section of Metabolic Diseases, Children's Hospital of Philadelphia, 3501 Civic Center Boulevard, Philadelphia, PA 19104, USA. dacok@email.chop.edu
authors.forename: Kristin
authors.initials: K
authors.lastname: D'Aco
authors.forename: Lisa
authors.initials: L
authors.lastname: Underhill
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Rangachari
authors.forename: Pamela
authors.initials: P
authors.lastname: Arn
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Cox
authors.forename: Roberto
authors.initials: R
authors.lastname: Giugliani
authors.forename: Torayuki
authors.initials: T
authors.lastname: Okuyama
authors.forename: Frits
authors.initials: F
authors.lastname: Wijburg
authors.forename: Paige
authors.initials: P
authors.lastname: Kaplan
mesh_terms: D002675:Child, Preschool; D003131:Combined Modality Therapy; D057210:Delayed Diagnosis / Q000639:trends; D056947:Enzyme Replacement Therapy; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007068:Iduronidase / Q000627:therapeutic use; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008059:Mucopolysaccharidosis I / Q000175:diagnosis / Q000628:therapy; D010641:Phenotype; D010818:Practice Patterns, Physicians' / Q000639:trends*; D012042:Registries; D016896:Treatment Outcome
chemical_list: D007068:Iduronidase