• Journal of mucopolysaccharidosis and rare diseases
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• v.5 no.1
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• pp.34-38
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• 2021

Prader-Willi syndrome is a complicated genetic disorder caused by a mutation on chromosome 15q11-13. The disease results in morbid obesity due to hyperphagia, growth disturbance, multiple endocrine problems from hypopituitarism, developmental delay, and cognitive or behavioral problems. Recombinant human growth hormone has been used to improve body composition and muscle mass, which plays a main role in treating patients with Prader-Willi syndrome. We describe previous studies showing the efficacy and safety of growth hormone treatment in children with Prader-Willi syndrome and provide treatment guidelines. Growth hormone therapy could be beneficial for children with Prader-Willi syndrome and improve their quality of life.

• Journal of mucopolysaccharidosis and rare diseases
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• v.5 no.1
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• pp.22-28
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• 2021

Mucopolysaccharidosis type III (MPS III) or Sanfilippo disease is an orphan-inherited lysosomal storage disease. It is one of the most common MPS subtypes. The classical presentation is an infantile-onset neurodegenerative disease characterized by intellectual regression, behavioral and sleep disturbances, loss of ambulation, and early death. Unlike other MPS, no disease-modifying therapy has been approved. Here, we review the curative therapy developed for MPS III, from historically ineffective hematopoietic stem cell transplantation and substrate reduction therapy to the promising enzyme replacement therapy or adeno-associated/lentiviral vector-mediated gene therapy. Preclinical studies are presented with recent translational first-in-man trials. We also present experimental research with preclinical mRNA and gene-editing strategies. Lessons from animal studies and clinical trials have highlighted the importance of early therapy before extensive neuronal loss. Disease-modifying therapy for MPS III will likely mandate the development of new early diagnosis strategies.

• Journal of mucopolysaccharidosis and rare diseases
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• v.5 no.1
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• pp.12-16
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• 2021

Mucopolysaccharidosis type II (MPS II, Hunter syndrome) is an X-linked lysosomal storage disorder caused by deficiency of the enzyme iduronate-2-sulfatase, leading to the accumulation of glycosaminoglycans (GAGs), which affects multiple organs and systems. Current treatments for MPS II include enzyme replacement therapy (ERT) and hematopoietic cell transplantation (HCT) to reduce the accumulation of GAGs. HCT has the potential advantage that donor-derived enzyme-competent cells can provide a continuous secreting source of the enzyme. However, HCT as a treatment for MPS II remains controversial because its effectiveness is unclear, particularly in terms of neurological symptoms. To date, several clinical experiences with HCT in MPS II have been reported. In this paper, we review post-HCT outcomes in the previously published literature and discuss the effects of HCT on each of the clinical signs and symptoms of MPS II.

• Journal of mucopolysaccharidosis and rare diseases
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• v.3 no.1
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• pp.33-33
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• 2017

• Journal of mucopolysaccharidosis and rare diseases
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• v.3 no.1
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• pp.28-32
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• 2017

Lipoid congenital adrenal hyperplasia (LCAH) is the severe form of congenital adrenal hyperplasia and is characterized by adrenal insufficiency with hyperpigmentation and female external genitalia irrespective of genetic sex. The steroidogenic acute regulatory protein (StAR) is required for the transport of cholesterol into the mitochondria for steroidogenesis, and defects in the StAR gene account for the majority of LCAH cases. In this report, we present a two-day-old hyperpigmented infant with phenotypical female genitalia. With consideration of the clinical and laboratory findings, the infant was suspected of having adrenal insufficiency due to LCAH and treated with glucocorticoid, mineralocorticoid, and sodium chloride. Karyotyping revealed 46, XY. Upon pelvis ultrasonography, adrenal hyperplasia with abdominal masses (thought to be the testicles) was reported. Molecular analysis with targeted exome sequencing revealed the homozygote mutation of c.772C>T ($p.Q258^*$) in exon 7 of the StAR gene. The early detection and treatment of adrenal insufficiency in infants with hyperpigmentation can prevent clinically apparent adrenal crises. During follow-up, the patient had a good clinical condition and maintained normal electrolyte and adrenocorticotropic hormone levels with medication.

• Journal of mucopolysaccharidosis and rare diseases
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• v.3 no.1
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• pp.14-19
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• 2017

Lysosomal storage diseases (LSDs) are a group of rare inherited metabolic disorders caused by the deficiency of specific lysosomal enzymes and subsequent accumulation of substrates. Enzyme deficiency leads to progressive intra-lysosomal accumulation of the incompletely degraded substances, which cause dysfunction and destruction of the cell and eventually multiple organ damage. Patients have a broad spectrum of clinical phenotypes which are generally not specific for some LSDs, leading to missed or delayed diagnosis. Due to the availability of treatment including enzyme replacement therapy (ERT) and hematopoietic stem cell transplantation for some LSDs, early diagnosis is important. ERT products have been approved with optimal outcomes for some LSDs in the recent decades, including Gaucher, Fabry, mucopolysaccharidosis (MPS) I, Pompe, MPS VI, MPS II, and MPS IVA diseases. ERT can stabilize the clinical condition, prevent disease progression, and improve the long-term outcome of these diseases, especially if started prior to irreversible organ damage. Based on the availability of therapy and suitable screening methods in the recent years, some LSDs, including Pompe, Fabry, Gaucher, MPS I, MPS II, and MPS VI diseases have been incorporated into nationwide newborn screening panels in Taiwan.

• Journal of mucopolysaccharidosis and rare diseases
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• v.1 no.2
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• pp.44-48
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• 2015

Body fat distribution in patients with Prader-Willi syndrome (PWS) is characterized by reduce lean body mass (LBM), increased total body fat mass (FM), and lower percentage of visceral adipose tissue (VAT). Individuals with PWS seem to have a lower risk for insulin resistance with high levels of adiponectin, an anti-atherogenic adipocytokine that is decreased in visceral fat hypertrophy subjects compared to simple obese subjects, both in children and in adults. The mechanism of the reduction in visceral adiposity in PWS is still unclear. It might be related to qualitative intrinsic characteristics of adipocyte or novel genetic influences on the control of fat distribution. However, obesity remains a critical problem, and obesity status plays a crucial role in individual metabolic risk clustering and development of metabolic syndrome (Mets) in PWS children and adults. Long-term growth hormone (GH) treatment after cessation of skeletal growth improved body composition, with an increase in lean body mass and a reduction in total body fat and subcutaneous and visceral fat in PWS adults. Thus, the role of GH is important after childhood because it might attenuate obesity and Mets in PWS adult by adipocyte modification.

• Journal of mucopolysaccharidosis and rare diseases
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• v.1 no.2
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• pp.35-39
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• 2015

Sleep problems occur frequently among patients with Prader-Willi syndrome (PWS). The most common problem is excessive daytime sleepiness (EDS) that are closely related to of sleep-related breathing disorder (SRBD) such as obstructive sleep apnea (OSA) and congenital hypoventilation syndrome. Obesity, craniofacial dysmorphism and muscular hypotonia of patients with PWS may increase the risk of SRBD. Sleep apneas can interrupt the continuity of sleep, and these disruptions result in a decrease in both the quality and quantity of sleep. In addition to SRBD, other sleep disorders have been reported, such as hypersomnia, a primary abnormality of the rapid eye movement (REM) sleep and narcolepsy traits at sleep onset REM sleep. Patients with PWS have intrinsic abnormalities of sleep-wake cycles due to hypothalamic dysfunction. The treatment of EDS and other sleep disorders in PWS are similar to standard treatments. Correction of sleep hygiene such as sufficient amount of sleep, maintenance of regular sleep-wake rhythm, and planned naps are important. After comprehensive evaluation of sleep disturbances, CPAP or surgery should be recommended for treatment of SRBD. Remaining EDS or narcolepsy-like syndrome are controlled by stimulant medication. Bright light therapy might be beneficial for disturbed circadian sleep-wake rhythm caused by hypothalamic dysfunction.

• Journal of mucopolysaccharidosis and rare diseases
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• v.4 no.1
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• pp.21-25
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• 2018

Fabry disease is a hereditary lysosomal storage disorder caused by the reduction or absence of lysosomal enzyme alpha-galactosidase A and the accumulation of glycosphingolipids, such as globotriaosylceramide (Gb3), in various organs, including the heart. The prevention of cardiac involvement in Fabry disease can only be achieved by enzyme replacement therapy (ERT), and the method of assessing the efficacy of ERT should be confirmed. Changes in the electrocardiogram, such as the shortening of PQ interval, prolongation of QTc and repolarization abnormalities as well as left ventricular hypertrophy in voltage criteria, can be used to identify Fabry disease patients; however, the usefulness of electrocardiograms for evaluating the efficacy of ERT is limited. The assessment of left ventricular hypertrophy using echocardiography has been established to evaluate the efficacy of ERT during long-term period. A new technique involving speckled tracking method might be useful for detecting early cardiac dysfunction and identifying the effect of ERT for a relatively short period. The estimation of left ventricular hypertrophy using cardiac magnetic resonance (CMR) is also useful for assessing the efficacy of ERT. Identifying late gadolinium enhancement in CMR may affect the effectiveness of ERT, and the new technique of T1 mapping might be useful for monitoring the accumulation of Gb3 during ERT. Histopathology in cardiac biopsy specimens is another potentially useful method for identifying the accumulation of GB3; however, the use of histopathology to evaluate of the efficacy of ERT is limited because of the invasive nature of an endomyocardial biopsy.

• Journal of mucopolysaccharidosis and rare diseases
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• v.4 no.1
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• pp.7-10
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• 2018

Rare diseases are life threatening or chronically debilitating diseases with a low prevalence (less than 2,000 people in a population), which includes lysosomal storage diseases. These diseases are often seen as unimportant especially in developing countries, such as Indonesia, due to small number of patients. National Rare Disease Center in Indonesia was pioneered almost 20 years ago and officially established in 2017 by the Indonesian Minister of Health. Lysosomal storage disease become the most commonly found inborn errors of metabolism (IEM) in Indonesia due to easily accessible diagnostic facilities. Currently there are 7 patients receiving ERT in this mixed-donation scheme, one patient with Gaucher disease and 6 patients with MPS type II. Few challenges for ERT in Indonesia include importation through special access scheme, preparation of ERT infusion in intensive care settting, and cost of treatment. Even with limited resources, healthcare professionals in Indonesia have been giving the best care possible for rare disease patients, especially to provide diagnostic facilities through collaboration and treatment options for treatable rare diseases. Improvements in care for rare disease patients are still needed.