PURPOSE: The mucopolysaccharidoses (MPSs) are a heterogeneous group of lysosomal storage disorders. They are caused by a deficiency of the enzymes involved in the degradation of glycosaminoglycans. Early recognition is important because recombinant enzyme replacement therapy is now available for MPS. We studied the clinical characteristics of 80 MPS children with the object of determining the epidemiological, clinical and radiological features in Korean MPS children. METHODS: Diagnosis of MPS was confirmed by skin fibroblast enzyme analysis in 80 patients between February 1995 and December 2004. Charts were retrospectively reviewed for clinical and radiological findings, as well as for intelligence and speech evaluations. RESULTS: Hunter syndrome (MPS type II) was the most prevalent type, appearing in 51/80 cases (64 %), followed by Sanfilippo syndrome (MPS III-18%), Hurler syndrome (MPS I-15%), and Morquio syndrome (MPS IV-4%). The average age at diagnosis was 5.5 years (range 1 to 20), and the male-to-female ratio was 4.7: 1. Typical radiographic changes were observed in 45/54 cases (83%). Mitral regurgitation was the most common cardiac defect. Moderate to profound mental retardation and hearing loss were present in 14/35 cases (56%) and 33/38 cases (82%), respectively. Four MPS II patients had bone marrow transplantation, with mixed outcomes. Five MPS I patients are currently on enzyme replacement therapy. CONCLUSION: Our study showed a high proportion of MPS II cases (64%), which may represent population variability. By studying the clinical features of these patients, we hope to alert pediatricians of the warning signs of MPS.
Bone Marrow Transplantation ; Child ; Diagnosis ; Enzyme Replacement Therapy ; Fibroblasts ; Glycosaminoglycans ; Hearing Loss ; Hope ; Humans ; Incidence ; Intellectual Disability ; Intelligence ; Korea ; Mitral Valve Insufficiency ; Mucopolysaccharidoses* ; Mucopolysaccharidosis I ; Mucopolysaccharidosis II ; Mucopolysaccharidosis III ; Mucopolysaccharidosis IV ; Retrospective Studies ; Skin

Consensus ; Humans ; Mucopolysaccharidoses/therapy* ; Mucopolysaccharidosis IV ; Mucopolysaccharidosis VI

Morquio syndrome is a subtype of mucopolysaccharidoses, wherein the accumulation of glycosaminoglycans (GAGs) in various organ systems lead to alteration of anatomy and physiology. Most prominent features are extensive bony abnormalities, which normally require surgical correction. This paper reports the case of a 7-year-old child with Morquio syndrome who successfully underwent correction of genu valgum under general endotracheal anesthesia via asleep induction and videolaryngoscopy, with supplemental peripheral nerve block. The precautions and anesthetic care done to ensure a safe procedure are discussed, especially with anticipation of a possible difficult airway.
Mucopolysaccharidosis IV ; Mucopolysaccharidoses ; Anesthesia

Objective: To analyze the clinical characteristics of patients with Mucopolysaccharidosis ⅣA (MPS ⅣA). Methods: A retrospective study was conducted on 111 patients with MPS ⅣA in Xinhua Hospital of Shanghai Jiao Tong University School of Medcine from December 2008 to August 2020, confirmed by enzyme activity and genetic testing. General situation, clinical manifestations and enzyme activity test results were analyzed. According to the clinical manifestations, it can be divided into severe, intermediate and mild group. The independent sample <i>ti> test was used to compare the birth body length and weight of children with that of normal boys and girls, and group comparisons of enzyme activities were evaluated by median test. Results: One hundred and eleven unrelated patients, 69 males and 42 females, were classified into 3 subtypes: severe (<i>ni>=85), intermediate (<i>ni>=14), and mild (<i>ni>=12). The age at symptom onset were 1.6 (1.0, 3.0) years, and at diagnosis were 4.3 (2.8, 7.8) years. Skeletal manifestations were observed in all patients and consisted mainly of pectus carinatum (96/111, 86.5%), motor dysfunction (78/111, 70.3%), spinal deformity (71/111, 64.0%), growth retardation (64/111, 57.7%), joint laxity (63/111, 56.8%) and genu valgum (62/111, 55.9%). Eighty-eight patients (88/111, 79.3%) with MPS ⅣA were also along with non-skeletal manifestations, mainly including snoring (38/111, 34.2%), coarse faces (34/111, 30.6%), and visual impairment (26/111, 23.4%). The most common skeletal manifestation was pectus carinatum (79 cases), and non-skeletal manifestation was snoring (30 cases) and coarse faces (30 cases) in severe patients, pectus carinatum (13 cases) and snoring (5 cases) in intermediate type, motor dysfunction (11 cases) and snoring (3 cases) and visual impairment (3 cases) in mild patients. The height and weight of severe patients began to fall below -2 <i>si> at 2-<5 years and 5-<7 years, respectively. At the age of 10-<15 years, the standard deviation score of the height of severe patients reached (-6.2±1.6) <i>si> in males and (-6.4±1.2) <i>si> in females, and the score of weight got (-3.0±1.1) <i>si> in males and (-3.5±0.5) <i>si> in females. The height of intermediate patients began to fall below -2 <i>si> at the age of 7-<10 years, and the standard deviation score of height were -4.6 <i>si> and -3.6 <i>si> in 2 males, and -4.6 <i>si> and -3.8 <i>si> in 2 females at the age of 10-<15 years. The weight remained within -2 <i>si> in 72.0% (18/25) of intermediate patients compared to age-matched healthy children. In the mild patients with MPS ⅣA, the mean standard deviation score of height and weight was within -2 <i>si>. The enzyme activities of mild patients (2.02 (1.05, 8.20) nmol/(17 h·mg)) were both significantly higher than that of intermediate (0.57 (0.47, 0.94) nmol/(17 h·mg)) and severe (0.22 (0, 0.59) nmol/(17 h·mg)) patients (<i>Zi>=9.91, 13.98, <i>Pi>=0.005, 0.001), and the enzyme activity of intermediate patients was significantly higher than that of severe patients (<i>Zi>=8.56, <i>Pi>=0.010). Conclusions: The clinical manifestations of MPS ⅣA are charactered by pectus carinatum, motor function impairment, spinal deformity and growth retardation. The clinical characteristics, growth rate and enzyme activity differ among the 3 subtypes of MPS ⅣA.
Male ; Child ; Female ; Humans ; Adolescent ; Mucopolysaccharidosis IV ; Pectus Carinatum ; Retrospective Studies ; Snoring ; China ; Mucopolysaccharidoses ; Growth Disorders ; Vision Disorders

PURPOSE: Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is a rare lysosomal storage disorder caused by iduronate-2-sulfatase (IDS) deficiency. MPS II causes a wide phenotypic spectrum of symptoms ranging from mild to severe. IDS activity, which is measured in leukocyte pellets or fibroblasts, was reported to be related to clinical phenotype by Sukegawa-Hayasaka et al. Measurement of residual plasma IDS activity using a fluorometric assay is simpler than conventional measurements using skin fibroblasts or peripheral blood mononuclear cells. This is the first study to describe the relationship between plasma IDS activity and clinical phenotype of MPS II. METHODS: We hypothesized that residual plasma IDS activity is related to clinical phenotype. We classified 43 Hunter syndrome patients as having attenuated or severe disease types based on clinical characteristics, especially intellectual and cognitive status. There were 27 patients with the severe type and 16 with the attenuated type. Plasma IDS activity was measured by a fluorometric enzyme assay using 4-methylumbelliferyl-alpha-iduronate 2-sulphate. RESULTS: Plasma IDS activity in patients with the severe type was significantly lower than that in patients with the attenuated type (P=0.006). The optimal cut-off value of plasma IDS activity for distinguishing the severe type from the attenuated type was 0.63 nmol.4 hr-1.mL-1. This value had 88.2% sensitivity, 65.4% specificity, and an area under receiver-operator characteristics (ROC) curve of 0.768 (ROC curve analysis; P=0.003). CONCLUSION: These results show that the mild phenotype may be related to residual lysosomal enzyme activity.
Enzyme Assays ; Fibroblasts ; Humans ; Iduronate Sulfatase ; Leukocytes ; Mucopolysaccharidoses ; Mucopolysaccharidosis II ; Phenotype ; Plasma ; Sensitivity and Specificity ; Skin

PURPOSE: Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is a rare lysosomal storage disorder caused by iduronate-2-sulfatase (IDS) deficiency. MPS II causes a wide phenotypic spectrum of symptoms ranging from mild to severe. IDS activity, which is measured in leukocyte pellets or fibroblasts, was reported to be related to clinical phenotype by Sukegawa-Hayasaka et al. Measurement of residual plasma IDS activity using a fluorometric assay is simpler than conventional measurements using skin fibroblasts or peripheral blood mononuclear cells. This is the first study to describe the relationship between plasma IDS activity and clinical phenotype of MPS II. METHODS: We hypothesized that residual plasma IDS activity is related to clinical phenotype. We classified 43 Hunter syndrome patients as having attenuated or severe disease types based on clinical characteristics, especially intellectual and cognitive status. There were 27 patients with the severe type and 16 with the attenuated type. Plasma IDS activity was measured by a fluorometric enzyme assay using 4-methylumbelliferyl-alpha-iduronate 2-sulphate. RESULTS: Plasma IDS activity in patients with the severe type was significantly lower than that in patients with the attenuated type (P=0.006). The optimal cut-off value of plasma IDS activity for distinguishing the severe type from the attenuated type was 0.63 nmol.4 hr-1.mL-1. This value had 88.2% sensitivity, 65.4% specificity, and an area under receiver-operator characteristics (ROC) curve of 0.768 (ROC curve analysis; P=0.003). CONCLUSION: These results show that the mild phenotype may be related to residual lysosomal enzyme activity.
Enzyme Assays ; Fibroblasts ; Humans ; Iduronate Sulfatase ; Leukocytes ; Mucopolysaccharidoses ; Mucopolysaccharidosis II ; Phenotype ; Plasma ; Sensitivity and Specificity ; Skin

Hunter syndrome is one of the mucopolysaccharidoses, characterized by abnormal accumulation and deposition of mucopolysaccharides in the tissues of several organs which are known to complicate anaesthetic and airway management. We experienced a case of pulmonary edema which developed during induction of general anesthesia of Hunter syndrome after several attempts of intubation and airway obstruction.
Airway Management ; Airway Obstruction ; Anesthesia, General ; Glycosaminoglycans ; Intubation ; Intubation, Intratracheal* ; Mucopolysaccharidoses ; Mucopolysaccharidosis II* ; Pulmonary Edema*

Mucopolysaccharidosis type III (MPS III) is a rare genetic disorder caused by lysosomal storage of heparan sulfate. MPS IIIB results from a deficiency in the enzyme alpha-N-acetyl-D-glucosaminidase (NAGLU). Affected patients begin showing behavioral changes, progressive profound mental retardation, and severe disability from the age of 2 to 6 years. We report a patient with MPS IIIB with a long-term follow-up duration. He showed normal development until 3 years. Subsequently, he presented behavioral changes, sleep disturbance, and progressive motor dysfunction. He had been hospitalized owing to recurrent pneumonia and epilepsy with severe cognitive dysfunction. The patient had compound heterozygous c.1444C>T (p.R482W) and c.1675G>T (p.D559Y) variants of NAGLU. Considering that individuals with MPS IIIB have less prominent facial features and skeletal changes, evaluation of long-term clinical course is important for diagnosis. Although no effective therapies for MPS IIIB have been developed yet, early and accurate diagnosis can provide important information for family planning in families at risk of the disorder.
Diagnosis ; Epilepsy ; Family Planning Services ; Follow-Up Studies ; Heparitin Sulfate ; Humans ; Intellectual Disability ; Lysosomal Storage Diseases ; Mucopolysaccharidoses* ; Mucopolysaccharidosis III* ; Pneumonia

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.
Early Diagnosis ; Echocardiography ; Extremities ; Hip ; Humans ; Leukocytes ; Mucopolysaccharidoses ; Mucopolysaccharidosis IV ; Phenotype ; Quality of Life ; Respiratory Function Tests ; Retrospective Studies ; Spinal Cord Diseases ; Stress, Psychological

Glycogen storage disease (GSD) and mucopolysaccharidosis (MPS) are both independently inherited disorders. GSD is a member of a group of genetic disorders involving enzymes responsible for the synthesis and degradation of glycogen. GSD leads to abnormal tissue concentrations of glycogen, primarily in the liver, muscle, or both. MPS is a member of a group of inherited lysosomal storage diseases, which result from a deficiency in specific enzymatic activities and the accumulation of partially degraded acid mucopolysaccharides. A case of a 16-month-old boy who presented with hepatomegaly is reported. The liver was four finger-breadth-palpable. A laboratory study showed slightly increased serum AST and ALT levels. The liver biopsy showed microscopic features compatible with GSD. The liver glycogen content was 9.3% which was increased in comparison with the reference limit, but the glucose-6-phosphatase activity was within the normal limit. These findings suggested GSD other than type I. Bony abnormalities on skeletal radiographs, including an anterior beak and hook-shaped vertebrae, were seen. The mucopolysaccharide concentration in the urine was increased and the plasma iduronate sulfatase activity was low, which fulfilled the diagnosis criteria for Hunter syndrome (MPS type II). To the best of the authors' knowledge, this is the first case of GSD and Hunter syndrome being identified at the same time.
Animals ; Beak ; Biopsy ; Glucose-6-Phosphatase ; Glycogen ; Glycogen Storage Disease ; Glycosaminoglycans ; Hepatomegaly ; Humans ; Iduronate Sulfatase ; Infant ; Liver ; Liver Glycogen ; Lysosomal Storage Diseases ; Mucopolysaccharidoses ; Mucopolysaccharidosis II ; Muscles ; Plasma ; Spine