ABSTRACT
Mucopolysaccharidosis VI (MPS VI) is a clinically heterogeneous and progressive disorder with multiorgan manifestations caused by deficient N-acetylgalactosamine-4-sulfatase activity. A cross-sectional Survey Study in individuals (n = 121) affected with MPS VI was conducted between 2001 and 2002 to establish demographics, urinary glycosaminoglycan (GAG) levels, and clinical progression of disease. We conducted a Resurvey Study (ClinicalTrials.gov: NCT01387854) to obtain 10-year follow-up data, including medical histories and clinical assessments (n = 59), and survival status over 12 years (n = 117). Patients received a mean (SD) of 6.8 (2.2) years of galsulfase ERT between baseline (Survey Study) and follow-up. ERT patients increased in height by 20.4 cm in the 4-7-year-old baseline age group and by 16.8 cm in the 8-12-year-old baseline age group. ERT patients <13 years-old demonstrated improvement in forced vital capacity (FVC) by 68% and forced expiratory volume in 1 sec (FEV1) by 55%, and those ≥13 years-old increased FVC by 12.8% and maintained FEV1. Patients with >200 µg/mg baseline uGAG levels increased FVC by 48% in the <13-year-old baseline age group and by 15% in the ≥13-year-old baseline age group. ERT patients who completed the 6-min walk test demonstrated a mean (SD) increase of 65.7 (100.6) m. Cardiac outcomes did not significantly improve or worsen. Observed mortality rate among naïve patients was 50% (7/14) and 16.5% (17/103) in the ERT group (unadjusted hazard ratio, 0.24; 95% CI, 0.10-0.59). Long-term galsulfase ERT was associated with improvements in pulmonary function and endurance, stabilized cardiac function and increased survival.
Subject(s)
Enzyme Replacement Therapy , Mucopolysaccharidosis VI/drug therapy , N-Acetylgalactosamine-4-Sulfatase/therapeutic use , Adolescent , Body Weights and Measures , Child , Child, Preschool , Cross-Sectional Studies , Exercise Test , Female , Follow-Up Studies , Heart Function Tests , Humans , Male , Mucopolysaccharidosis VI/mortality , Mucopolysaccharidosis VI/urine , N-Acetylgalactosamine-4-Sulfatase/urine , Quality of Life , Recombinant Proteins/therapeutic use , Recombinant Proteins/urine , Respiratory Function Tests , Young AdultABSTRACT
A mucopolissacaridose tipo VI (MPS VI) é uma doença rara causada pela deficiência da enzima lisossômica arilsulfatase B, com consequente acúmulo de glicosaminoglicanos (GAGs) em vários tecidos, incluindo o cardiovascular. Com o objetivo de descrever as manifestações cardiovasculares na MPS VI, uma das principais causas de óbito, seis pacientes (4 a 13 anos) foram avaliados por exame físico, eletrocardiograma e ecocardiograma. Todos os pacientes, exceto a paciente com a menor idade, apresentaram sopro cardíaco e alterações ecocardiográficas. Os 6/6 pacientes apresentaram, no eletrocardiograma, desvio do eixo cardíaco para a direita, associado à sobrecarga atrial esquerda (1/6) ou distúrbio de condução (1/6).
Subject(s)
Humans , Male , Female , Adult , Metabolism, Inborn Errors/complications , Mitral Valve Insufficiency/complications , Mitral Valve Insufficiency/diagnosis , Mucopolysaccharidosis VI/complications , Mucopolysaccharidosis VI/mortality , Echocardiography/methods , Echocardiography , Electrocardiography/methods , ElectrocardiographyABSTRACT
Mucopolysaccharidosis VI (MPS VI, Maroteaux-Lamy Syndrome) is one of approximately 50 known lysosomal storage disorders. MPS VI is characterized by an absence or deficiency of N-acetylgalactosamine 4-sulfatase (arylsulfatase B) resulting in accumulation of dermatan sulfate. Prior to the availability of enzyme replacement therapy (ERT), the clinical management of MPS VI was limited to supportive care and allogeneic hematopoietic stem cell transplantation (HSCT); however, due to the rarity of this disease, little is known about the long-term outcomes of HSCT for MPS VI. The following retrospective study was performed using aggregate data gathered by the Center for International Blood and Marrow Transplant Research (CIBMTR) between 1982 and 2007 to determine survival probability for patients with MPS VI following allogeneic HSCT. This analysis identified 45 MPS VI patients with a median age of 5 years (range, 1-22 years) at the time they received an allogeneic HSCT. Cumulative incidence (95% CI) of acute graft-vs.-host disease at 100 days was 36% (21-53%). Probability of survival was 78% (65-89%) at 100 days and 66% (52-79%) at 1 and 3 years. While these data are based upon small numbers of recipients, they represent the largest series to date and may help clinicians assess the relative risks and benefits of currently available therapies.
