ABSTRACT
Abstract Data on Mucopolysaccharidosis type II (MPS II) in Latin America are scarce. This retrospective database study, using data from the Informatics Department of the Brazilian Health System (DATASUS), aimed to estimate the prevalence of MPSII in Brazil from 2008 to 2020 and to describe demographic and clinical profiles from patients under treatment. The study population was derived from DATASUS records of MPS II (ICD-10 E76.1) diagnosed in Brazil. Initially 455 patients were found, but only 181 patients who were receiving idursulfase treatment were included in this study. Among these cases, as expected in a X-linked disease, all were males and 40% of the cases were recorded in the Southeast region, and another 34% in the Northeast region. The biggest proportion of patients (39%) were diagnosed when they were 10-19 years old. There are 212 clinical conditions associated with MPS II, although the main comorbidities related to MPSII include: abdominal/inguinal hernia, respiratory complications, and carpal tunnel syndrome. Respiratory disorders were the fifth most frequent comorbidity recorded in these patients. The healthcare professionals in Brazil more involved in the diagnosis of MPS II were radiologists, followed by geneticists and cardiologists. Despite some limitations, DATASUS is a relevant database to provide information on rare diseases such as MPS II. Most cases were reported in southeast and northeast regions, respectively. This information is crucial to help design targeted public policies.
ABSTRACT
Mucopolysaccharidosis type II, also known as Hunter syndrome, is a rare, progressive, multisystemic lysosomal storage disease caused by de?ciency of iduronate 2 sulfatase, an enzyme responsible for the degradation of the mucopolysaccharides dermatan (DS) and keratan sulfate (QS), causing their accumulation at the lysosomal level. It is an X-linked disease, therefore it is common to ?nd most cases in men, rarely in women, it is considered an orphan disease given an incidence of approximately 1/100,000 live births. Various phenotypes of severe (2/3) and attenuated disease have been described. The diagnosis is based on clinical ?ndings and the measurement of mucopolysaccharides DS and QS in urine, which are elevated, con?rmed by determining the enzyme de?ciency in serum, leukocytes and ?broblasts. It has been observed that in patients with enzyme replacement therapy somatic symptoms have decreased, however there are several studies of alternative therapies in the future, including gene therapy as an alternative in the future
ABSTRACT
Abstract Mucopolysaccharidosis II (MPS II—Hunter syndrome) is an X-linked lysosomal storage disorder caused by a deficiency in iduronate-2 sulfatase. Enzyme replacement therapy does not cross the blood-brain barrier (BBB), limiting the results in neurological forms of the disease. Another treatment option for MPS, hematopoietic stem cell transplantation (HSCT) has become the treatment of choice for the severe form of MPS I since it can preserve neurocognition when performed early in the course of the disease. Even though the intravenous therapy does not cross the BBB, it has become the recommended treatment for MPS II, and HSCT was not often indicated. In an attempt to understand why this treatment modality is rejected by most specialists as a treatment option for patients with Hunter syndrome, we sought to raise all HSCT cases already reported in the scientific literature. Databases used were Medline/PubMed, Lilacs/BVS Cochrane Library, DARE, SciELO, and SCOPUS. Different combinations of the terms "mucopolysaccharidosis II," "Hunter syndrome," "hematopoietic stem cell transplantation," "bone marrow transplantation," and "umbilical cord blood stem cell transplantation" were used. A total of 780 articles were found. After excluding redundant references and articles not related to the theme, 26 articles were included. A descriptive summary of each article is presented, and the main features are summed up. The clinical experience with HSCT in MPS II is small, and most of the available literature is outdated. The available data reveal poor patient selection criteria, varied conditioning regimens, distinct follow-up parameters, and post-HSCT outcomes of interest, making impossible to compare and generalize the results obtained. Recently, after the development of new conditioning protocols and techniques and the creation of bone marrow donor registries and umbilical cord banks, HSCT has become more secure and accessible. It seems now appropriate to reconsider HSCT as a treatment option for the neuronopathic form of MPS II.
ABSTRACT
La mucopolisacaridosis tipo II (MPS II) es un desorden recesivo ligado al cromosoma X, caracterizado por una deficiencia de la enzima iduronato-2-sulfatasa, que lleva a una afectación multisistémica por acumulación tisular de los glicosaminoglicanos heparan y dermatan sulfato. Reportamos el caso de un niño de 9 años diagnosticado con MPS II a los 4 años de edad, catalogado como portador de una variante grave. Presentó neumonía necrotizante asociada a infección A H1N1, que requirió ventilación mecánica por 1 mes y 10 días. Este caso enfatiza la importancia de que los trabajadores de la salud estén alerta a las potenciales complicaciones en pacientes con MPS II, tales como la infección por influenza A H1N1, la que, a su vez, puede estar asociada con neumonía necrotizante.
Mucopolysaccharidosis type II (MPS II) is an X-linked recessive disorder characterized by a deficiency of the enzyme iduronate-2-sulfatase leading to a multisystem involvement by tissue accumulation of glycosaminoglycans heparan and dermatan sulfate. We report a case of a 9-year-old boy diagnosed with mucopolysaccharidosis type II at 4 years of age, classified as severe variant. He presented necrotizing pneumonia associated with influenza A H1N1 infection, requiring mechanical ventilation for 1 month and 10 days. This case emphasizes the importance of healthcare workers to be aware of potentially lethal complications in patients with MPS II, such as influenza A H1N1 infection, which in turn may be associated with necrotizing pneumonia.