OBJECTIVETo investigate the clinical characteristics and diagnosis of mucopolysaccharidosis VII.

METHODThe clinical and biochemical features of an infant with mucopolysaccharidosis VII confirmed by enzyme assay were analyzed.

RESULTThe 2 month-old male infant showed hydrops fetalis, mental retardation, coarse face, corneal clouding, hepatosplenomegaly, hernias, Alder-Reilly granules in the leucocytes and decreased platelet (32 × 10(9)/L). The biochemical markers showed urinary glycosaminoglycans (GAG) (532.8 mg/L, controls < 70.0 mg/L). The ratio of GAG/creatinine was 161.3 (controls: 26.2 ± 11.7). Serum chitotriosidase activity was 315.8 nmol/(ml·h) [control < 53 nmol/(ml·h)]. Beta-glucuronidase activity was deficient in isolated leukocytes.

CONCLUSIONSevere form of mucopolysaccharidosis VII exhibited characteristics of hydrops fetalis, hepatosplenomegaly, coarse face, thrombocytopenia and Alder-Reilly granules in the leucocytes. The measurements of GAG in urinary and beta glucuronidase in leucocytes are critical to diagnosis and deferential diagnosis.

Glucuronidase ; metabolism ; Glycosaminoglycans ; urine ; Humans ; Infant ; Leukocytes ; enzymology ; Male ; Mucopolysaccharidosis VII

OBJECTIVETo explore the incidence of various types of mucopolysaccharidosis (MPS) and their clinical characteristics.

METHODSA total of 75 children highly suspected as having MPS underwent quantitative and electrophoretic analysis of urinary glycosaminoglycans (GAGs) and enzymatic analysis of seven types of MPS from January 2009 to December 2011. Fluorescence assay was used to measure the activities of α-L-iduronidase, iduronate-2-sulfatase, α-N-acetylglucosaminidase, galactosamine-6-sulfatase, β-galactosidase, arylsulfatase B and β-glucuronidase in the white blood cells.

RESULTSA total of 52 cases were confirmed with MPS based on clinical, radiological, and enzymatic examinations. The 52 cases, with a mean age of 4.0 ± 2.2 years, included 5 cases of MPS I (10%), 20 cases of MPS II (38%), 20 cases of MPS IVA (38%), 6 cases of MPS VI (12%) and 1 case of MPS VII (2%). No MPS IV B cases or MPS IIIB cases were found. Compared with healthy children of the same age, the GAG/Cr ratio was significantly elevated in 50 confirmed cases of MPS (two MPS IVA cases having no increased ratio). All children with increased urinary GAGs had a confirmed diagnosis of MPS. The age of onset was between 1 and 2 years after birth in most cases, and often complicated by hernia and valvular heart disease. Children with MPS I, MPS II, and MPS VI presented with ugly and unsmooth face, short stature, joint stiffness, and limitation of motion, while children with MPS IVA presented with short stature, skeletal dysplasia, and joint laxity.

CONCLUSIONSType IVA and type II are the most common in MPS cases, followed by type VI and type I. MPS children are characterized by special appearances including ugly and unsmooth facial appearance, short stature and skeletal dysplasia. Quantitative analysis of urinary GAG, as a simple, rapid, and reliable method, is recommended for screening of MPS.

Acetylglucosaminidase ; blood ; Child ; Child, Preschool ; Creatinine ; urine ; Female ; Glucuronidase ; blood ; Glycosaminoglycans ; urine ; Humans ; Iduronidase ; blood ; Infant ; Magnetic Resonance Imaging ; Male ; Mucopolysaccharidoses ; diagnosis ; enzymology ; pathology ; beta-Galactosidase ; blood

Mucopolysaccharidosis (MPS) III has 4 enzymatically distinct forms (A, B, C, and D), and MPS IIIC, also known as Sanfilippo C syndrome, is an autosomal recessive lysosomal storage disease caused by a deficiency of heparan acetyl-CoA:alpha-glucosaminide N-acetyltransferase (HGSNAT). Here, we report a case of MPS IIIC that was confirmed by molecular genetic analysis. The patient was a 2-yr-old girl presenting with skeletal deformity, hepatomegaly, and delayed motor development. Urinary excretion of glycosaminoglycan (GAG) was markedly elevated (984.4 mg GAG/g creatinine) compared with the age-specific reference range (<175 mg GAG/g creatinine), and a strong band of heparan sulfate was recognized on performing thin layer chromatography. HGSNAT enzyme activity in leukocytes was 0.7 nmol/17 hr/mg protein, which was significantly lower than the reference range (8.6-32 nmol/17 hr/mg protein). PCR and direct sequencing of the HGSNAT gene showed 2 mutations: c.234+1G>A (IVS2+1G>A) and c.1150C>T (p.Arg384*). To the best of our knowledge, this is the first case of MPS IIIC to be confirmed by clinical, biochemical, and molecular genetic findings in Korea.
Acetyltransferases/*genetics ; Asian Continental Ancestry Group/*genetics ; Base Sequence ; Child, Preschool ; Chromatography, Thin Layer ; Female ; Glycosaminoglycans/urine ; Heparitin Sulfate/chemistry/metabolism ; Humans ; Leukocytes/immunology/metabolism ; Mucopolysaccharidosis III/*diagnosis/genetics/radiography ; Mutation ; Republic of Korea ; Sequence Analysis, DNA

INTRODUCTIONRecommended by the National Advisory Council of the Disabled, the Ministry of Health of Singapore supported a nationwide study of inherited metabolic disorders (IMDs). When the 5-year project ended, investigations were provided as a diagnostic service. This paper documents our 13-year experience.

MATERIALS AND METHODSPatients with symptoms suggestive of an IMD were referred. Investigations on heparinised blood and/or urine included amino acid analysis using a Beckman 6300 Amino Acid Analyser, organic acids analysis using a Hewlett- Packard gas chromatography and mass spectrometry, mucopolysaccharides quantitative assay and high-resolution electrophoresis, sugars by thin-layer chromatography.

RESULTSOf the 3656 patients studied from 1992 to 2005, IMDs were found in 127 (77 males; 50 females; age range, 1 day to 56 years). Their ethnic distribution was: 55.1% Chinese, 19.7% Malays, 11.0% Indians, 11.0% other races and 3.2% unknown. IMD diagnosed comprised 41 (32.3%) organic acidurias, 34 (26.8%) amino acidaemias/acidurias, 14 (11.0%) urea cycle defects, 15 (11.8%) mucopolysaccharidoses, 6 (4.7%) carbohydrate disorders and 17 (13.4%) others. Twenty-three (18.1%) cases were diagnosed during the neonatal period and 36 (28.3%) after the age of 13.

CONCLUSIONPositive detection rate was 3.5% and 48 IMDs were found. Significant proportion of cases had late-onset IMDs. Early identification of IMDs permits timely management, genetic counselling and prenatal diagnosis.

Adolescent ; Adult ; Amino Acids ; metabolism ; Biomarkers ; blood ; cerebrospinal fluid ; urine ; Carbohydrates ; blood ; Child ; Child, Preschool ; Chromatography, Gas ; Female ; Follow-Up Studies ; Glycosaminoglycans ; metabolism ; Humans ; Infant ; Infant, Newborn ; Male ; Mass Spectrometry ; Metabolism, Inborn Errors ; epidemiology ; metabolism ; Middle Aged ; Prevalence ; Prognosis ; Retrospective Studies ; Singapore ; epidemiology ; Urea ; metabolism

OBJECTIVEMucopolysaccharidosis type VI (MPS VI) or Maroteaux-Lamy syndrome is an autosomal recessive lysosomal storage disease caused by a deficiency of arylsulfatase B(ARSB), which is required in the degradation of dermatan sulfate and chondroitin sulfate. The deficiency of ARSB leads to an accumulation of dermatan sulfate and chondroitin sulfate in lysosomes and gross excretion in the urine.Few articles about clinical study and ARSB gene mutation analysis of Chinese MPS VI patients were published. This study aimed to explore the clinical features and characteristics of ARSB gene in Chinese children with MPS VI.

METHODThirteen children were diagnosed as MPS VI by ARSB enzyme activity determination during the period from 2009 to 2013. Their clinical features, radiological findings and urine glycosaminoglycan (GAG) levels were retrospectively reviewed. Direct sequencing was used to identify any mutation in the ARSB gene.

RESULTThirteen children were diagnosed at the average age of (3.9 ± 2.2) years with 6 male and 7 female. All of these children presented with severe form and onset at an early age of (1.5 ± 0.8) years.Other clinical features included coarse facies, short stature, skeleton deformity, corneal clouding, hepatosplenomegaly with normal intelligence. The radiological findings in all children were characteristic of dysostosis multiplex, like abnormal development of vertebral bodies of the spine, campylorrhachia and paddle-shaped widened ribs. The MRI in case 2 showed cervical cord compression and multiple cysts degeneration in the corona radiate, cella lateralis and callosum.High urine GAG levels were detected, (307.10 ± 112.14) mg/L (Normally below 70 mg/L) and (722.28 ± 245.68) µg/mg creatinine. The ARSB enzyme activity in leukocytes was low, (13.29 ± 6.22) nmol/(mg×h) [Normal range (47-169) nmol/(mg×h)] by fluorogenic assay and (0.24 ± 0.18) U/g [Normal range (1.01-11.47) U/g] by colorimetric assay. A total of 11 mutations were identified by molecular analysis, including seven previously reported mutations (p.L72R, p.G167R, p.G303E, p.F399L, p. T442M, p.Y255X and p.R327X) and four novel mutations (p.Y175D, p.S403X, p.S464X and large deletion including ex. 2, 3). The c.1197C>G (p.F399L) mutation was the most common mutation in this study (31%).

CONCLUSIONThe severe form of MPS VI is characterized by early onset and rapid illness progression. Both the radiological findings and increased urine GAG are important clues to diagnose MPS VI.Large decrease or absence of ARSB activity is diagnostic for MPS VI.Four novel mutations of ARSB gene were identified. The reported mutation c.1197C>G (p.F399L) was the hot-spot mutation in this study.

Bone and Bones ; diagnostic imaging ; pathology ; Brain ; pathology ; Child ; Child, Preschool ; Exons ; genetics ; Female ; Glycosaminoglycans ; urine ; Humans ; Infant ; Magnetic Resonance Imaging ; Male ; Mucopolysaccharidosis VI ; diagnosis ; enzymology ; genetics ; Mutation ; N-Acetylgalactosamine-4-Sulfatase ; genetics ; metabolism ; Polymerase Chain Reaction ; Radiography ; Retrospective Studies ; Sequence Analysis, DNA