Different diseases, different needs: Patient preferences for gene therapy in lysosomal storage disorders, a probabilistic threshold technique survey.

BACKGROUND: Gene therapy is currently in development for several monogenetic diseases including lysosomal storage disorders. Limited evidence is available on patient preferences for gene therapy in this population. In this study, we compare gene therapy-related risk tolerance between people affected by three lysosomal storage diseases currently faced with different therapeutic options and prognoses. METHODS: A survey including the probabilistic threshold technique was developed in which respondents were asked to choose between gene therapy and the current standard of care. The attributes included to establish participants' risk tolerance were previously identified in focus groups of affected people or their representatives, namely: risk of mild side effects, severe side effects, the need for additional medication, and the likelihood of long-term effectiveness. The survey was distributed among people receiving outpatient care for type 1 Gaucher disease (good prognosis with current treatment options), Fabry disease (varying prognosis with current treatment options, XY-genotype on average more severely affected than XX), and parents representing people with severe forms of mucopolysaccharidosis type III A/B (poor prognosis, no disease-specific therapy available). RESULTS: A total of 85 surveys were completed (15 Gaucher disease respondents, 62 Fabry disease respondents (17 self-identifying male), eight parents of ten people with mucopolysaccharidosis type III). Disease groups with higher disease severity trended towards higher risk tolerance: Gaucher disease respondents were most cautious and predominantly preferred the current standard of care as opposed to MPS III representatives who were more risk tolerant. Respondents with Fabry disease were most heterogeneous in their risk tolerance, with male participants being more risk tolerant than female participants. Long-term effectiveness was the attribute in which respondents tolerated the least risk. CONCLUSIONS: People affected by a lysosomal storage disease associated with a poorer prognosis and less effective current treatment options trended towards more risk tolerance when choosing between gene therapy and the current standard of care. This study shows the importance of involvement of patient preferences before and during the development process of new treatment modalities such as gene therapy for rare diseases, to ensure that innovative therapies align with the wishes and needs of people affected by these diseases.

Inflammation and lipoperoxidation in mucopolysaccharidoses type II patients at diagnosis and post-hematopoietic stem cell transplantation.

INTRODUCTION: Mucopolysaccharidosis type II (MPS II) is caused by deficiency of the enzyme iduronate-2-sulfatase; one possible therapy for MPS II is hematopoietic stem cell transplantation (HSCT). It is established that there is excessive production of reactive species in MPS II patients, which can trigger several processes, such as the inflammatory cascade. OBJECTIVES: Our aim was to outline an inflammatory profile and lipoperoxidation of MPS II patients for a better understanding of disease and possible benefits that HSCT can bring in these processes. MATERIALS AND METHODS: We investigate oxidative damage to lipids by 15-F2t-isoprostane urinary concentrations and plasma pro-and anti-inflammatory cytokine concentrations in MPS II patients at diagnosis, MPS II post-HSCT patients, and controls. RESULTS: Interleukin (IL)-1ß and IL-17a concentrations were significantly increased and a tendency toward increased IL-6 production in the diagnosis group was verified. We found significant decrease in IL-4 and increase in 15-F2t-isoprostane concentrations in the diagnosis group, while IL-1ß, IL-6, IL-17a and 15-F2t-isoprostane concentrations were similar between control and post-HSCT groups. CONCLUSIONS: Our study demonstrated that MPS II patients at diagnosis are in a pro-inflammatory state, bringing a novel result showing increased production of IL-17a, an osteoclastogenic cytokine, as well as demonstrating that these patients have oxidative damage to lipids. Furthermore, evidence suggests that HSCT can reduce inflammation and lipoperoxidation in MPS II patients.

Respiratory insufficiency after brain metastasectomy for extraskeletal Ewing sarcoma in an adult patient with mucopolysaccharidosis type II: a case report.

Mucopolysaccharidosis is a rare lysosomal storage disease caused by deficiencies in enzymes involved in the degradation of glycosaminoglycans. We report the case of an adult with mucopolysaccharidosis type II who developed respiratory insufficiency after brain metastasectomy for extraskeletal Ewing sarcoma. This report describes the case of a 35-year-old man with a mass on the left chest wall for 3 months. Magnetic resonance imaging and computed tomography revealed a large mass on the chest wall. Positron emission tomography revealed multiple metastatic lesions in the lungs, ribs, and sternum. A needle biopsy specimen confirmed extraskeletal Ewing sarcoma, and the fusion gene EWS-FLI1 was positive. Subsequently, multidrug chemotherapy was administered. During radiotherapy for the primary lesion, progressive convulsions occurred suddenly. Computed tomography of the brain revealed metastasis in the frontal lobe. Brain metastasectomy was scheduled; however, endotracheal intubation was not possible because of the deformity of the glottis, and emergency tracheostomy was performed. Thereafter, granulation tissue proliferated in reaction to the tracheostomy cannulae in the trachea, and respiratory insufficiency persisted. Because of the rapid growth of an intrathoracic recurrent tumor, the patient passed away 2 months after brain surgery. This is the first report of sarcoma in a patient with mucopolysaccharidosis. Respiratory management is difficult in patients with mucopolysaccharidosis, especially under general anesthesia. Orthopedic surgeons should be aware that surgical planning must be performed carefully when soft tissue sarcomas occur in patients with mucopolysaccharidosis.

Intracranial tumor in a patient with mucopolysaccharidosis type 1 (Scheie syndrome): An extremely rare combination.

Scheie syndrome is a mild variant of mucopolysaccharidosis type I (MPS I), a rare group of lysosomal storage diseases that affect multiple organ systems. It is rarely associated with neoplasia. To the best of our knowledge, only a single case of mucopolysaccharidosis associated with a brain tumor has been reported, and it was nearly three decades ago. We present the case of a 10-year-old female with Scheie syndrome associated with a brain tumor. Physical and laboratory findings were suggestive of Scheie syndrome. A skeletal survey also revealed a spectrum of dysostosis multiplex supporting MPS. Children with MPS can have rapidly enlarging head sizes due to hydrocephalus, but our patient had several red flags that demanded further evaluation. A brain MRI revealed a mass in the fourth ventricle and a biopsy of the mass revealed pilocytic astrocytoma grade 1. Intraventricular pilocytic astrocytoma itself is a rare occurrence, accounting for only 4%-15.6 % of all pilocytic astrocytomas. Altered mucopolysaccharide metabolism can be involved in tumor pathogenesis, but the exact mechanism is unknown. Mucopolysaccharidoses, being a group of complicated disorders, are difficult to manage, and many symptoms can be missed in children due to intellectual disability. This case highlights the importance of suspecting brain tumors in children with mucopolysaccharidoses who present with signs and symptoms of increased intracranial pressure. Prompt diagnosis and management can save the child from dire neurological consequences.

The diagnosis and management of mucopolysaccharidosis type II.

Mucopolysaccharidosis type II (MPS II) is a rare X-linked recessive inherited lysosomal storage disease. With pathogenic variants of the IDS gene, the activity of iduronate-2-sulfatase (IDS) is reduced or lost, causing the inability to degrade glycosaminoglycans (GAGs) in cells and influencing cell function, eventually resulting in multisystemic manifestations, such as a coarse face, dysostosis multiplex, recurrent respiratory tract infections, and hernias. Diagnosing MPS II requires a combination of clinical manifestations, imaging examinations, urinary GAGs screening, enzyme activity, and genetic testing. Currently, symptomatic treatment is the main therapeutic approach. Owing to economic and drug availability issues, only a minority of patients opt for enzyme replacement therapy or hematopoietic stem cell transplantation. The limited awareness of the disease, the lack of widespread detection technology, and uneven economic development contribute to the high rates of misdiagnosis and missed diagnosis in China.

Body Height of MPS I and II Patients after Hematopoietic Stem Cell Transplantation: The Impact of Dermatan Sulphate.

INTRODUCTION: Hematopoietic stem cell transplantation (HSCT) comprises one of the two main treatment regimens for patients with mucopolysaccharidoses (MPS). There is a scarcity of literature concerning the process of growth in children with Mucopolysaccharidosis type I (MPS I) and Mucopolysaccharidosis type I (MPS II) after HSCT. The aim of this manuscript was to evaluate the therapeutic effect of HSCT on the heights of patients with MPS I and MPS II. MATERIAL AND METHODS: It was an observational, single-center study on patients with MPS I and II treated with HSCT. RESULTS: 6 MPS patients, including 4 MPS I and 2 MPS II, underwent HSCT at a median age of 2 years. All patients are alive to date, with a median age of 7.7 years (range 5.5-12 years) at the last follow-up. In both (MPS I and MPS II) groups of patients treated with HSCT, the growth rate was higher than in untreated patients and was found to be in line with the population norm. In both MPS I and MPS II patients who were treated with HSCT, normalization of urinary GAG excretion was observed. Additionally, no bands of DS and HS in GAG electrophoresis were visible. CONCLUSIONS: Both MPS I and MPS II patients presented height gain after HSCT compared to the curves of untreated patients. The absence of dermatan sulphate after HSCT could lead to normal growth in bone length.

Mucopolysaccharidosis-Plus Syndrome: Is This a Type of Mucopolysaccharidosis or a Separate Kind of Metabolic Disease?

Several years ago, dozens of cases were described in patients with symptoms very similar to mucopolysaccharidosis (MPS). This new disease entity was described as mucopolysaccharidosis-plus syndrome (MPSPS). The name of the disease indicates that in addition to the typical symptoms of conventional MPS, patients develop other features such as congenital heart defects and kidney and hematopoietic system disorders. The symptoms are highly advanced, and patients usually do not survive past the second year of life. MPSPS is inherited in an autosomal recessive manner and is caused by a homozygous-specific mutation in the gene encoding the VPS33A protein. To date, it has been described in 41 patients. Patients with MPSPS exhibited excessive excretion of glycosaminoglycans (GAGs) in the urine and exceptionally high levels of heparan sulfate in the plasma, but the accumulation of substrates is not caused by a decrease in the activity of any lysosomal enzymes. Here, we discuss the pathomechanisms and symptoms of MPSPS, comparing them to those of MPS. Moreover, we asked the question whether MPSPS should be classified as a type of MPS or a separate disease, as contrary to 'classical' MPS types, despite GAG accumulation, no defects in lysosomal enzymes responsible for degradation of these compounds could be detected in MPSPS. The molecular mechanism of the appearance of GAG accumulation in MPSPS is suggested on the basis of results available in the literature.

Evaluation of neuroretina following i.v. or intra-CSF AAV9 gene replacement in mice with MPS IIIA, a childhood dementia.

BACKGROUND: Sanfilippo syndrome (mucopolysaccharidosis type IIIA; MPS IIIA) is a childhood dementia caused by inherited mutations in the sulfamidase gene. At present, there is no treatment and children with classical disease generally die in their late teens. Intravenous or intra-cerebrospinal fluid (CSF) injection of AAV9-gene replacement is being examined in human clinical trials; evaluation of the impact on brain disease is an intense focus; however, MPS IIIA patients also experience profound, progressive photoreceptor loss, leading to night blindness. AIM: To compare the relative efficacy of the two therapeutic approaches on retinal degeneration in MPS IIIA mice. METHODS: Neonatal mice received i.v. or intra-CSF AAV9-sulfamidase or vehicle and after 20 weeks, biochemical and histological evaluation of neuroretina integrity was carried out. RESULTS: Both treatments improved central retinal thickness; however, in peripheral retina, outer nuclear layer thickness and photoreceptor cell length were only significantly improved by i.v. gene replacement. Further, normalization of endo-lysosomal compartment size and microglial morphology was only observed following intravenous gene delivery. CONCLUSIONS: Confirmatory studies are needed in adult mice; however, these data indicate that i.v. AAV9-sulfamidase infusion leads to superior outcomes in neuroretina, and cerebrospinal fluid-delivered AAV9 may need to be supplemented with another therapeutic approach for optimal patient quality of life.

Use of Marsupialization as a Definitive Treatment for Large-sized Dentigerous Cysts in a Patient with Mucopolysaccharidosis Type I.

The correct diagnosis is fundamental for the appropriate treatment to be employed in a particular pathology. The best treatment is not the one that solves only local problems, fragmenting the patient, and therefore, it is necessary to integrate the entire systemic condition of the individual before initiating any local treatment. This context inevitably requires dentistry to participate in a multidisciplinary approach, where the role of the dentist is expanded in concepts that encompass ethics, human dignity, and professional valorization. This article describes a clinical case of a patient with mucopolysaccharidosis type I, whose treatment of cystic lesions present in the mandible was exclusively performed through marsupialisation. The objective of this study is to demonstrate, within the complexity of this rare syndrome, the difficulties of diagnosis and the need for evaluation of the patient beyond the limits of the oral cavity, as well as to report two cases of large dentigerous cysts, surgically treated conservatively through marsupialisation, without the need for re-approach for enucleation and without recurrences over a 20-year period.

Design and validation of a GMP stem cell manufacturing protocol for MPSII hematopoietic stem cell gene therapy.

Hematopoietic stem cell gene therapy (HSCGT) is a promising therapeutic strategy for the treatment of neurodegenerative, metabolic disorders. The approach involves the ex vivo introduction of a missing gene into patients' own stem cells via lentiviral-mediated transduction (TD). Once transplanted back into a fully conditioned patient, these genetically modified HSCs can repopulate the blood system and produce the functional protein, previously absent or non-functional in the patient, which can then cross-correct other affected cells in somatic organs and the central nervous system. We previously developed an HSCGT approach for the treatment of Mucopolysaccharidosis type II (MPSII) (Hunter syndrome), a debilitating pediatric lysosomal disorder caused by mutations in the iduronate-2-sulphatase (IDS) gene, leading to the accumulation of heparan and dermatan sulfate, which causes severe neurodegeneration, skeletal abnormalities, and cardiorespiratory disease. In HSCGT proof-of-concept studies using lentiviral IDS fused to a brain-targeting peptide ApoEII (IDS.ApoEII), we were able to normalize brain pathology and behavior of MPSII mice. Here we present an optimized and validated good manufacturing practice hematopoietic stem cell TD protocol for MPSII in preparation for first-in-man studies. Inclusion of TEs LentiBOOST and protamine sulfate significantly improved TD efficiency by at least 3-fold without causing adverse toxicity, thereby reducing vector quantity required.

Enzymatic testing for mucopolysaccharidosis type I in Kuwaiti newborns: a preliminary study toward newborn screening.

Mucopolysaccharidosis type I (MPS I) is an autosomal recessive lysosomal storage disorder characterized by deficient or absent α-L-iduronidase (IDUA) enzyme activity due to pathogenic variants in the IDUA gene. Early treatment with hematopoietic stem cell transplantation and/or enzyme replacement therapy is associated with improved outcomes in this progressive multisystem disease. The diagnosis is usually delayed due to late presentation and non-specific symptoms, which result in high morbidity and mortality. The incidence of MPS I is unknown in Kuwait. This pilot study was undertaken to screen MPS I in all Kuwaiti neonates born at Farwaniya Hospital (FH), a major center in Kuwait, over 12 months. This study examined the incidence of MPS I for inclusion in the national newborn screening (NBS) to enable its early detection and adequate treatment. All Kuwaiti neonates born at FH between December 2021 and December 2022 were screened for MPS I. The screening consisted of determining IDUA enzyme activity in dried blood spot-derived samples using tandem mass spectrometry. A follow-up genetic analysis of the IDUA gene has been planned to screen the cases with diminished IDUA enzyme activity as second-tier testing. A total of 618 newborns, including 331 (54%) boys and 287 (46%) girls, were screened. Of them, 20 had deficient IDUA enzyme activity but showed negative genetic testing. However, we have diagnosed one additional female infant with MPS I who belonged to FH, but the parents chose to deliver in a private hospital. The molecular genetic study revealed the presence of a previously reported pathogenic nonsense variant in the IDUA c.1882C>T, which is associated with severe phenotype. That being included, MPS I is estimated to be approximately 0.2% of all screened cases in Kuwait. Our study is the first to evaluate the incidence of MPS I in Kuwait. Given the single center, small number of screened infants, and the short study duration thus far, it is premature to calculate the incidence. It is anticipated that as the study continues, we would be able to estimate the incidence in our population correctly. Screening newborns in all maternity hospitals in Kuwait is necessary to calculate the actual incidence of this severe disorder. Still, our preliminary data support the inclusion of MPS I in national NBS program to allow early initiation of treatment and thus improve disease outcome.

AAV gene replacement therapy for treating MPS IIIC: Facilitating bystander effects via EV-mRNA cargo.

MPS IIIC is a lysosomal storage disease caused by mutations in heparan-α-glucosaminide N-acetyltransferase (HGSNAT), for which no treatment is available. Because HGSNAT is a trans-lysosomal-membrane protein, gene therapy for MPS IIIC needs to transduce as many cells as possible for maximal benefits. All cells continuously release extracellular vesicles (EVs) and communicate by exchanging biomolecules via EV trafficking. To address the unmet need, we developed a rAAV-hHGSNATEV vector with an EV-mRNA-packaging signal in the 3'UTR to facilitate bystander effects, and tested it in an in vitro MPS IIIC model. In human MPS IIIC cells, rAAV-hHGSNATEV enhanced HGSNAT mRNA and protein expression, EV-hHGSNAT-mRNA packaging, and cleared GAG storage. Importantly, incubation with EVs led to hHGSNAT protein expression and GAG contents clearance in recipient MPS IIIC cells. Further, rAAV-hHGSNATEV transduction led to the reduction of pathological EVs in MPS IIIC cells to normal levels, suggesting broader therapeutic benefits. These data demonstrate that incorporating the EV-mRNA-packaging signal into a rAAV-hHGSNAT vector enhances EV packaging of hHGSNAT-mRNA, which can be transported to non-transduced cells and translated into functional rHGSNAT protein, facilitating cross-correction of disease pathology. This study supports the therapeutic potential of rAAVEV for MPS IIIC, and broad diseases, without having to transduce every cell.

Delayed diagnosis of mild mucopolysaccharidosis type IVA.

BACKGROUND: Mucopolysaccharidosis IVA (MPS IVA) is a lysosomal storage disease caused by biallelic variants in the N-acetylgalactosamine-6-sulfatase (GALNS) gene and is characterized by progressive and multi-system involvements, dominantly with skeletal deformities. A mild form of MPS IVA often presents with atypical symptoms and can go unrecognized for years. METHODS: The diagnosis of MPS IVA was confirmed via GALNS enzyme activity testing in leukocytes. Clinical features were collected. Molecular analysis was performed by next generation sequence and Sanger sequencing of the GALNS gene. The pathogenicity of the deep intron variant was verified by mRNA analyses. RESULTS: Thirteen patients with mild MPS IVA from six families were included. All probands first visit pediatric orthopedists and it took 5.6 years to be diagnosed after the disease onset. The most common symptoms in our series were waddling gait (85%), short neck (69%) and flat feet (62%). Radiologic findings indicated skeletal abnormalities in all patients, especially modification of the vertebral bodies (100%) and acetabular and femoral head dysplasia (100%). Five novel GALNS variants, including c.121-2_121-1insTTTGCTGGCATATGCA, E2 deletion, c.569 A > G, c.898 + 2 T > A, and c.1139 + 2 T > C, were identified. The most common variant, a deep intron variant NM_000512.5: c.121-210 C > T (NM_001323544.2: c.129 C > T, p.G43G), was revealed to result in an 11 bp deletion (c.128_138delGCGATGCTGAG, p.Gly43Aspfs*5) on GALNS mRNA in the GALNS transcript of NM_001323544.2. CONCLUSIONS: This study provides significant insights into the clinical features and molecular characteristics that contribute to the early diagnosis of mild MPS IVA. On the basis of our cohort, orthopedists need to be able to recognize signs and symptoms of mild MPS IVA as well as the molecular and biochemical diagnosis so that an early diagnosis and treatment can be instituted.

Molecular therapy and nucleic acid adeno-associated virus-based gene therapy delivering combinations of two growth-associated genes to MPS IVA mice.

Mucopolysaccharidosis type IVA (MPS IVA) is caused by a deficiency of the galactosamine (N-acetyl)-6-sulfatase (GALNS) enzyme responsible for the degradation of specific glycosaminoglycans (GAGs). The progressive accumulation of GAGs leads to various skeletal abnormalities (short stature, hypoplasia, tracheal obstruction) and several symptoms in other organs. To date, no treatment is effective for patients with bone abnormalities. To improve bone pathology, we propose a novel combination treatment with the adeno-associated virus (AAV) vectors expressing GALNS enzyme and a natriuretic peptide C (CNP; NPPC gene) as a growth-promoting agent for MPS IVA. In this study, an MPS IVA mouse model was treated with an AAV vector expressing GALNS combined with another AAV vector expressing NPPC gene, followed for 12 weeks. After the combination therapy, bone growth in mice was induced with increased enzyme activity in tissues (bone, liver, heart, lung) and plasma. Moreover, there were significant changes in bone morphology in CNP-treated mice with increased CNP activity in plasma. Delivering combinations of CNP and GALNS gene therapies enhanced bone growth in MPS IVA mice more than in GALNS gene therapy alone. Enzyme expression therapy alone fails to reach the bone growth region; our results indicate that combining it with CNP offers a potential alternative.

Safe and effective liver-directed AAV-mediated homology-independent targeted integration in mouse models of inherited diseases.

Liver-directed adeno-associated viral (AAV) vector-mediated homology-independent targeted integration (AAV-HITI) by CRISPR-Cas9 at the highly transcribed albumin locus is under investigation to provide sustained transgene expression following neonatal treatment. We show that targeting the 3' end of the albumin locus results in productive integration in about 15% of mouse hepatocytes achieving therapeutic levels of systemic proteins in two mouse models of inherited diseases. We demonstrate that full-length HITI donor DNA is preferentially integrated upon nuclease cleavage and that, despite partial AAV genome integrations in the target locus, no gross chromosomal rearrangements or insertions/deletions at off-target sites are found. In line with this, no evidence of hepatocellular carcinoma is observed within the 1-year follow-up. Finally, AAV-HITI is effective at vector doses considered safe if directly translated to humans providing therapeutic efficacy in the adult liver in addition to newborn. Overall, our data support the development of this liver-directed AAV-based knockin strategy.

Further characterization of ARSK-related mucopolysaccharidosis type 10.

Mucopolysaccharidosis type 10 is caused by biallelic variants in ARSK, which encodes for a lysosomal sulfatase. To date, seven patients with a mild phenotype resembling spondyloepiphyseal dysplasia or multiple epiphyseal dysplasia have been described. In this report, we present two novel ARSK variants and report clinical and radiological findings of three patients. The patients' initial complaints were hip or knee pain and a waddling gait. All patients showed normal intelligence, normal hearing and eye examinations, and none had organomegaly. While typical dysostosis multiplex findings were not observed, mild platyspondyly with anterior beaking of some vertebral bodies, irregular vertebral endplates, wide ribs, inferior tapering of the ilea with a poorly developed acetabulum, irregularity of the central part of the femoral head, delayed ossification of the carpals were noted. Remarkably, all patients showed metaphyseal striation of the long bones, a crucial diagnostic clue to identify ARSK-related MPS type 10. Interestingly, vertebral involvement regressed during follow-up. On the other hand, hip dysplasia progressed in all patients. In conclusion, this study provides valuable long-term results on a recently discovered form of MPS.

Airway and Anaesthetic Management of Adult Patients with Mucopolysaccharidoses Undergoing Cardiac Surgery.

Background: Mucopolysaccharidoses (MPSs) are rare congenital lysosomal storage disorders due to a deficiency of enzymes metabolising glycosaminoglycans, leading to their accumulation in tissues. This multisystem disease often requires surgical intervention, including valvular cardiac surgery. Adult MPSs have complex airways making anaesthesia risky. Methods: We report novel three-dimensional (3D) modelling airway assessments and multidisciplinary peri-operative airway management. Results: Five MPS adults underwent cardiac surgery at the national MPS cardiac centre (type I = 4, type II = 1; ages 20, 24, 33, 35, 37 years; two males, three females). All had complex airway abnormalities. Assessments involved examination, nasendoscopy, imaging, functional studies, 3D reconstruction, virtual endoscopy, virtual reality and simulation using computerised, physical modelling. Awake oral fibre-optic intubation was achieved via airway conduit. Staged extubation was performed on the first post-operative day under laryngo-tracheoscopic guidance. The post-operative period involved chest physiotherapy and occupational therapy. All patients had safe intubation, ventilation and extubation. Four had good cardiac surgical outcomes, one (MPS type I; age 35 years) was inoperable due to endocarditis. None had post-operative airway complications. Conclusions: Expertise from cardiovascular-heart team, multidisciplinary airway management, use of novel techniques is vital. Traditional airway assessments are insufficient, so ENT input, radiology and computerised methods to assess and simulate the airway in 3D by collaboration with clinical engineering is essential.

Morquio A Syndrome: Identification of Differential Patterns of Molecular Pathway Interactions in Bone Lesions.

Mucopolysaccharidosis type IVA (MPS IVA; Morquio A syndrome) is a rare autosomal recessive lysosomal storage disease (LSD) caused by deficiency of a hydrolase enzyme, N-acetylgalactosamine-6-sulfate sulfatase, and characterized clinically by mainly musculoskeletal manifestations. The mechanisms underlying bone involvement in humans are typically explored using invasive techniques such as bone biopsy, which complicates analysis in humans. We compared bone proteomes using DDA and SWATH-MS in wild-type and MPS IVA knockout mice (UNT) to obtain mechanistic information about the disease. Our findings reveal over 1000 dysregulated proteins in knockout mice, including those implicated in oxidative phosphorylation, oxidative stress (reactive oxygen species), DNA damage, and iron transport, and suggest that lactate dehydrogenase may constitute a useful prognostic and follow-up biomarker. Identifying biomarkers that reflect MPS IVA clinical course, severity, and progression have important implications for disease management.

Hand Radiographs in Skeletal Dysplasia: A Pictorial Review.

Skeletal dysplasias or osteochondrodysplasias comprise a large heterogeneous group of genetic disorders and possess significant overlap on imaging, which adds to the dilemma of the reporting radiologist. These entities are routinely evaluated with a detailed skeletal survey and hand radiographs form a crucial part of a complete survey. Certain conditions have characteristic imaging findings that enable a diagnosis be made on hand radiograph alone. Additionally, hand radiographs may also demonstrate findings that may be suggestive of a particular diagnosis/differential diagnoses and would warrant further assessment for proving the same. We aim to demonstrate the use of hand radiographs in diagnosis of various such entities through this review. Although they cannot replace a complete skeletal survey in the diagnosis, hand radiographs performed for other indications might alert a radiologist to the diagnosis of an unsuspected skeletal dysplasia.

Adenotonsillectomy for the treatment of OSA in children with mucopolysaccharidosis: A systematic review.

OBJECTIVE: To study the role of adenotonsillectomy (ADT) for obstructive sleep apnea (OSA) in children with mucopolysaccharidosis (MPS). METHODS: A systematic review were performed following the PRISMA guideline. PubMed and Embase were searched for studies regarding adenotonsillectomy for OSA in children with MPS. The MINOR Score were applied for quality assessment of the included studies. RESULTS: Nineteen studies were eligible for inclusion: fifteen were retrospective and four prospective. A total of 1406 subjects were included. The samples size varied from 2 to 336, the male to female ratio is 1.2 and mean age varied from 2.4 to 11 years. Overall, 56.2 % (IC 95%: 53.6-58.8) of the included subjects underwent ADT. MPS I and II are the two most operated types. Three studies, including 50 children, reported improvement in polysomnographic parameters after surgery. Two authors described the duration of follow-up: 8.4 and 9.8 years, respectively. CONCLUSIONS: More than half of children with MPS underwent ADT for the treatment of OSA, although few evidence demonstrated improvement in term of polysomnographic parameters. The two types of MPS most involved are type I and II. Considering the disease progression and anesthetic risks, multidisciplinary management may help identify the subgroup of children with MPS who benefit from ADT for the treatment of OSA.