Clinical and treatment of 2 children with severe mucopolysaccharidosis type ⅣA from 2 pedigrees and prenatal diagnosis for their sibling / 中华实用儿科临床杂志

Objective:To explore the treatment of the patients with severe phenotype of mucopolysaccharidosis (MPS) type ⅣA by analysing the clinical feature and diagnosis.Methods:Two pediatric patients diagnosed as MPS ⅣA in severe form were enrolled in Children′s Hospital Affiliated to Zhengzhou University from August 2021 to April 2022.Two children from 2 pedigrees with the main manifestations of short stature and bone deformities were retrospectively included.The clinical manifestations, biochemical indexes, and bone imaging findings were retrospectively analyzed.Peripheral blood leukocytes were collected and subjected to the N-acetylgalactosamine-6-sulfatase (GALNS) assay and genetic sequencing.Gene analysis of amniotic fluid cells at the 18 th week of the second pregnancy of the mother of case 2 was performed for prenatal diagnosis.Allogeneic hematopoietic stem cell transplantation (allo-HSCT) was performed in both patients and to explore the treatment of patients with MPS ⅣA. Results:Both cases presented clinical manifestations of short stature, joint laxity, pectus carinatum, and genu valgus.X-ray examination revealed the decreased bone mineral density, ulnar deviation of the radial epiphysis, kyphosis and scoliosis.The respiratory and skeletal systems were affected in both patients, and the optic nerve was suspiciously affected. GALNS gene analysis showed that there were 2 missense mutations of c. 1019G>A (p.G340D) and c. 706C>G (p.H236D) in case 1, and 2 missense mutations of c. 425A>G (p.H142R) and c. 463G>A (p.G155R) were detected in case 2.Mutations in both cases were inherited from their fathers and mothers, which were all newly discovered that have not been reported.Only the c. 463G>A mutation was detected in the amniotic fluid cells of the mother of case 2.It is confirmed that case 2 was the carrier of MPS ⅣA, whose gene mutation was from the mother, and case 2 did not suffer the same disease as the proband.Both cases were treated with allo-HSCT with full donor chimerism and no severe transplant complications were reported.Their GALNS activity was within the normal range, and the scores of activities of daily living were higher than those before transplantation. Conclusions:The MPS ⅣA patients with severe phenotype is a rare autosomal recessive disease caused by GALNS mutations that is difficult to diagnose and poor prognosis.Early detection, diagnosis, and effective treatment contribute to improve the long-term quality of life.The allo-HSCT is an effective therapeutic strategy for MPS ⅣA.

Perthes-Like Disease Masquerading Non-Classical MPS

Abstract Mucopolysaccharidoses (MPS) are inborn errors of metabolism caused by deficient lysosomal enzymes, leading to organomegaly, hip osteonecrosis, coarse facial features, bone deformities, joint stiffness, cardiac and pulmonary symptoms (MPS VI) or hypermobility (MPS IVA). Some patients may present with non-classical forms of the disease in which osteoarticular abnormalities are the initial symptoms of non-classical forms. As orthopedists and surgeons are the specialists most frequently consulted before the diagnosis, it is critical that MPS may be considered as a differential diagnosis for patients with bone dysplasia. Experts in Latin America reviewed medical records focusing on disease onset, first symptoms and the follow-up clinical and surgical outcomes of non-classical MPS VI and IVA patients. All patients displayed orthopedic issues, which worsened over time, followed by cardiac and ophthalmological abnormalities. Our findings enlighten the necessity of including non-classical MPS as possible diagnosis for patients who report osteoarticular abnormalities in absence of inflammation.

Safety and Efficacy of Elosulfase Alfa in Australian Patients with Morquio a Syndrome: A Phase 3b Study

Abstract The safety and efficacy of elosulfase alfa were evaluated in a multicenter, open-label, phase 3b study in Australian Morquio A patients, consisting of a 49-week initial phase and an extension phase until elosulfase alfa was government funded. Thirteen patients (1-27 years) were enrolled. No new safety concerns were identified over 138 weeks. Most drug-related adverse events were mild or moderate in severity; none led to study discontinuation. After 49 weeks of treatment, median improvements from baseline were seen in the 6-minute walk test (+41.0 m), 3-minute stair climb test (+14.0 stairs/min), forced vital capacity (+16.4%), forced expiratory volume in 1 second (+14.1%), urine keratan sulfate (-7.1 µg/mg creatinine), and pain intensity. Growth, cardiac function, sleep, and quality of life results were mixed or stable. These results provide further evidence of the acceptable safety/tolerability profile of elosulfase alfa. The improvements in endurance, pulmonary function, and pain support findings from previous studies.

Impact of Elosulfase Alfa on Pain in Patients with Morquio A Syndrome over 52 Weeks: MOR-008: A Randomized, Double-Blind, Pilot Study

Abstract Patients with mucopolysaccharidosis (MPS), and Morquio A syndrome (MPS IVA) in particular, often report substantial pain burden. MOR-008 was a randomized, double-blind, pilot study assessing the safety and efficacy, including impact on patient-reported pain, of 52 weeks of treatment with elosulfase alfa (at a dose of 2.0 or 4.0 mg/kg/week) in patients with Morquio A syndrome (?7 years old). Assessment of pain at baseline revealed that patients (N = 25) had a mean number of pain locations of 5.7, mean pain intensity score of 4.6 (indicative of medium pain), and a mean number of selected pain descriptors of 7.4 words. Treatment with elosulfase alfa improved subjective pain score (reduced to 3.2), pain locations (reduced by a mean of 1 location), and pain descriptor words (reduced to 4.9 words) over 1 year (52 weeks), suggesting that elosulfase alfa can reduce pain in some patients with Morquio A.

Relationship Between Patient-Reported Outcomes and Clinical Outcomes in Patients With Morquio A Syndrome

Abstract This cross-sectional analysis assessed the correlation between patient-reported outcomes (PROs) and clinical outcomes in 24 German patients with Morquio A. Clinical outcomes included 6-minute walk test (6MWT), 3-minute stair climb (3MSC) test, and joint range of motion as measures for endurance/mobility, forced vital capacity (FVC) and maximum voluntary ventilation (MVV) as measures for respiratory function, and height as an important manifestation. The PROs included the EuroQoL (EQ) 5D-5L (EQ5D-5L), to measure health-related QoL (HRQoL), and patients' rating of their ability to walk, climb, or breathe. In adults, endurance and pulmonary function measures and height showed strong and statistically significant correlation with the patients' EQ5D-5L (6MWT: R = .884, 3MSC test: R = .852, FVC: R = .815, MVV: R = .825, height: R = .842). The adult patients' rating of their ability to walk and climb also correlated strongly with 6MWT (R = .839) and 3MSC test (R = .700) results. Improvements in these clinical outcomes may be robust surrogate parameters of a better EQ5D-5L/HRQoL in patients with Morquio A.

Enzyme Replacement Therapy With Elosulfase Alfa Decreases Storage of Glycosaminoglycan in White Blood Cells of Patients With Morquio A Syndrome

Abstract Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is a lysosomal storage disorder caused by a deficient N-acetylgalactosamine-6-sulfate sulfatase activity, leading to cellular storage of undegraded keratan sulfate. Recently enzyme replacement therapy (ERT) was approved for MPS IVA, but some of ERT effects are still unknown. In the present study, we aimed to evaluate the efficacy of elosulfase alfa upon glycosaminoglycan (GAG) storage in peripheral blood white blood cells of patients with MPS IVA treated for 6 months, comparing samples from patients who received weekly infusions of enzyme (ERT-W) versus infusions every other week (ERT-EOW) versus placebo. A significant reduction in GAG storage was observed in both ERT-treated groups, with weekly ERT showing slightly better performance than ERT-EOW.

Presentación de un caso clínico de mucopolisacaridosis Tipo IV, síndrome de Morquio / Presentation of a clinical case of mucopolysaccharidosis type IV, Morquio syndrome

Se presenta el caso de un paciente de 16 años de edad, con el diagnostico de mucopolisacaridosis (MPS) tipo IV-A, con una breve revisión teórica del curso y progresión crónica de esta enfermedad multi-sistémica, que se manifiesta con amplia signo sintomatología, hallazgos de laboratorio y anomalías radiológicas. El objetivo es documentar el caso y difundir a la comunidad médica boliviana, la importancia de los errores innatos del metabolismo, consideradas enfermedades "raras", que a criterio nuestro, sufren un sub-diagnóstico debido a las pocas publicaciones científicas sobre el tema en el medio.

We report the case of a patient 16 years old with a diagnosis of mucopolysaccharidosis (MPS) type IV- A, with a brief theoretical review of chronic course and progression of this multisystem disease, which manifests with extensive signs symptoms, findings are presented, with laboratory and radiological reported abnormalities. The aim is to document the event and communicated to Bolivian medical community, the importance of inborn errors of metabolism, considered "rare" diseases, which in our opinion; suffer a sub- diagnosis because of the few Bolivian scientific publications on the topic.

The Burden Endured by Caregivers of Patients With Morquio A Syndrome: Results From an International Patient-Reported Outcomes Survey

Abstract This international survey performed by direct personal interview or mail evaluated the global burden among primary caregivers of patients with Morquio A syndrome. Collected outcomes included self-reported time spent on caregiving, proportion of daily activities (from the Mucopolysaccharidosis Health Assessment Questionnaire) requiring caregiver assistance, and how the patient's age and wheelchair use affect these. In addition, the impact of caregiving on the caregivers' relationship with family and friends, physical and mental health, and employment status and income was evaluated. Caregiver burden increased with disease progression. Adult patients always using a wheelchair required substantially more caregiving time and complete assistance with a larger proportion of daily activities than more mobile patients. In children, this was less apparent. Caregivers suffered physically and emotionally and their family and social life and financial situation were considerably impacted. Improvements in patient mobility may substantially reduce the level of caregiver support and the burden of caregiving.

Clinical, radiologic, and genetic features of Korean patients with Mucopolysaccharidosis IVA / 소아과

PURPOSE: Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is rare lysosomal storage disorder caused by N-acetylgalactosamine-6-sulfatase (GALNS) deficiency. Only a few MPS IVA cases have been reported in the Korean literature; there is a paucity of research about clinical or radiologic findings for this disorder. Therefore, we studied clinical findings, radiological features, and genetic data of Korean MPS IVA patients for determining factors that may allow early diagnosis and that may thus improve the patients' quality of life. METHODS: MPS IVA was confirmed via assay for enzymatic activity of leukocytes in 10 patients. The GALNS gene was analyzed. Patients' charts were retrospectively reviewed for obtaining clinical features and evaluated for radiological skeletal surveys, echocardiography, pulmonary function test, and ophthalmologic test results. RESULTS: Nine patients had severe clinical phenotype, and 1 had an intermediate phenotype, on the basis of clinical phenotype criteria. Radiologic findings indicated skeletal abnormalities in all patients, especially in the hips and extremities. Eight patients had an odontoid hypoplasia, and 1 showed mild atlantoaxial subluxation and cord myelopathy. Genetic analysis indicated 10 different GALNS mutations. Two mutations, c.451C>A and c.1000C>T, account for 37.5% (6/16) and 25% (4/16) of all mutations in this samples, respectively. CONCLUSION: An understanding of the clinical and radiological features involved in MPS IVA may allow early diagnosis of MPS IVA. Adequate evaluations and therapy in the early stages may improve the quality of life of patients suffering from skeletal abnormalities and may reduce life-threatening effects of atlantoaxial subluxation.

Uso de vectores derivados de virus adenoasociados para el tratamiento de la enfermedad de Morquio A / Adenoassociated virus-derived vectors for the treatment of Morquio A disease

En el desarrollo de una estrategia de terapia génica para la mucopolisacaridosis IV A (enfermedad de Morquio A), en el presente trabajo se evaluó la capacidad de un vector adenoasociado (AAV) para expresar el gen de la enzima sulfatasa N-acetilgalactosamina-6-sulfato (GALNS, N-acetylgalactosamine-6-sulfate sulfatase) en células HEK293, fibroblastos humanos con mucopolisacaridosis IV A y condrocitos de ratón con mucopolisacaridosis IV A. En el lisado celular, la actividad de la GALNS se incrementó entre 5 y 24 veces los valores observados en las células sin transfectar. La coexpresión con el gen del factor activador de sulfatasas 1 (SUMF1, sultatase modifiying factor 1) permitió un incremento en la actividad de la GALNS en el lisado celular de hasta 4,5 veces los valores observados en las células cotransfectadas con AAV-GALNS. La actividad de la GALNS en el medio de cultivo sólo se detectó en células cotransfectadas con AAV-SUMF1. Estos resultados constituyen evidencia valiosa sobre la posibilidad de realizar la corrección del defecto genético en la mucopolisacaridosis IV A empleando vectores AAV...

Toward the development of a gene therapy strategy for the mucopolysaccharidosis IV A (MPS IV A, Morquio A), in this work we evaluated the capability of an AAV vector to express the N-acetilgalactosamine-6-sulfate sulfatase (GALNS) gene in HEK293 cells, human mucopolysaccharidosis IV A fibroblasts and murine MPS IV A chondrocites. GALNS activity in lysated cells was increased between 5 and 24 folds compared to nontransfected cells. Also, the effect of coexpression with the sultatase modifiying factor 1 (SUMF1) was evaluated.GALNS activity was increased up to 4.5 folds in lysated cells compared to those values observed in AAV-GALNS transduced cells. Noteworthy, enzyme activity was only detected in culture media when cells were cotransfected with AAV-GALNS and AAV-SUMF1. These results represent a valuable step in the development of a gene therapy strategy for mucopolysaccharidosis IV A using AAV vectors...