| Two brothers with oligosymptomatic mucopolysaccharidosis vii were observed from age 11 8/12 to 16 years, and 15 1/2 to 19 years, respectively. Asymptomatic thoracic kyphosis and mild scoliosis were the prominent clinical features. Herniae, hepatosplenomegaly, corneal clouding and shortness of stature were absent. Both had Alder type granulations in polymorphonuclear leukocytes and to a lesser degree in monocytes. Ultrastructural analysis of blood leukocytes revealed polymorphous inclusions of probably more than one class of organic substances. Radiological signs were mild, confined to the spine and consisted of irregularities of upper and lower vertebral plates, of vertebral flattening and some osteophytic changes. Both patients excreted excessive amounts of acid mucopolysaccharides in urine and also globoside. Cultured skin fibroblasts of both patients contained metachromatic granules, had only approx. 10% of normal beta-glucuronidase activity and degraded sulfated mucopolysaccharides at a slower than normal rate. Sera of the patients had none or minimal beta-glucuronidase activity, the mother's serum had subnormal and the father's serum low-normal activity. The older brother is the oldest known case of mucopolysaccharidosis vii. As this hereditary disorder may take a remarkably mild clinical course, beta-glucuronidase-deficient juveniles may exist undetected in the general population. ( info) |
2/138. Mutations in HYAL1, a member of a tandemly distributed multigene family encoding disparate hyaluronidase activities, cause a newly described lysosomal disorder, mucopolysaccharidosis IX. Hyaluronan (HA), a large glycosaminoglycan abundant in the extracellular matrix, is important in cell migration during embryonic development, cellular proliferation, and differentiation and has a structural role in connective tissues. The turnover of HA requires endoglycosidic breakdown by lysosomal hyaluronidase, and a congenital deficiency of hyaluronidase has been thought to be incompatible with life. However, a patient with a deficiency of serum hyaluronidase, now designated as mucopolysaccharidosis IX, was recently described. This patient had a surprisingly mild clinical phenotype, including notable periarticular soft tissue masses, mild short stature, an absence of neurological or visceral involvement, and histological and ultrastructural evidence of a lysosomal storage disease. To determine the molecular basis of mucopolysaccharidosis IX, we analyzed two candidate genes tandemly distributed on human chromosome 3p21.3 and encoding proteins with homology to a sperm protein with hyaluronidase activity. These genes, HYAL1 and HYAL2, encode two distinct lysosomal hyaluronidases with different substrate specificities. We identified two mutations in the HYAL1 alleles of the patient, a 1412G --> A mutation that introduces a nonconservative amino acid substitution (Glu268Lys) in a putative active site residue and a complex intragenic rearrangement, 1361del37ins14, that results in a premature termination codon. We further show that these two hyaluronidase genes, as well as a third recently discovered adjacent hyaluronidase gene, HYAL3, have markedly different tissue expression patterns, consistent with differing roles in HA metabolism. These data provide an explanation for the unexpectedly mild phenotype in mucopolysaccharidosis IX and predict the existence of other hyaluronidase deficiency disorders. ( info) |
3/138. chondroitin 4- and 6-sulfate mucopolysaccharidosis--a morphological study. A 17-year-old patient clinically manifesting gargoyle face, dwarfism, skeletal bone deformity, mild mental retardation and benign course was presented. Biochemically, increased urinary excretion of acidic glycosaminoglycans was confirmed and chondroitin 4-sulfate and chondroitin 6-sulfate were substantiated to be the major components of the acid mucopolysacchariduria. light microscopically, variable numbers of foam cells were observed in the biopsy materials of the lymph nodes, liver and skin, as well as in the smears of bone marrow aspirates. In the liver, the parenchymal cells appeared vacuolated. Histochemically, accumulation of sulfated acid glycosaminoglycans was demonstrated in the cytoplasm of the foam cells proliferating in these tissues, as well as in the liver cells. Electron microscopically, all of these storage cells were found to contain numerous, membrane-bound, vacuolar inclusions filled with flocculent, finely reticulogranular materials of low electron density similar to those seen in the storage cells of Hurler, Hunter or Sanfilippo's syndrome. Empty vacuoles were often coexistent. Accordingly, this case should be termed "chondroitin 4- and 6-sulfate mucopolysaccharidosis", with emphasis on the possibility of a new type of genetic mucopolysaccharidosis. ( info) |
4/138. Two cases of mucopolysaccharidosis type III (Sanfilippo). A biochemical study. The mucopolysaccharide and lipid composition of human nervous tissue and viscera from one case of Sanfilippo disease type A and one case of Sanfilippo disease type C, were investigated. In the brain a moderate increase of acid glycosaminoglycans occurred. This phenomenon was much more pronounced in the viscera, especially in the liver. In all tissues this increase was mainly due to an accumulation of heparan sulphate. Changes in lipid composition were noted, but can be regarded as secondary effects. The biochemical results reported also suggest some general conclusions. (a) AGAG and lipid analyses do not permit differentiation between the subtypes of Sanfilippo disease. (b) The differences in lipid composition can probably be considered as consequences of variation in secondary effects. (c) The severe demyelination in brain correlates well with the biochemical lipid analysis. However, in other instances it remains difficult to bridge the gap still existing between some morphological and biochemical data. ( info) |
| A new genetic variant of the Sanfilippo syndrome due to deficiency of acetyl CoA: alpha-glucosaminide N-acetyltransferase, was recently demonstrated in four patients. The clinical findings of these patients are reported here. Differential diagnosis from other types of the Sanfilippo syndrome on clinical and routine laboratory criteria is difficult and enzyme assay is necessary to reach the diagnosis. Since two of the patients reported are females and consanguinity was present in one case, autosomal recessive inheritance is most probable. ( info) |
6/138. chondroitin 4- and 6-sulfaturia: a new type of inborn error of metabolism? A 14-year-old boy was found to excrete excessive amounts of acidic glycosaminoglycans which were predominantly chondroitin 4-sulfate and chondroitin 6-sulfate. Clinical features included dwarfism, mental retardation, coarse facies, deformities of the spine, hip joints and thorax, and granulations in leucocytes. The clinical and biochemical features found in this boy were compared with the known types of mucopolysaccharidosis and it has been concluded that this case is a new type of mucopolysacchariduria. ( info) |
7/138. Treatment of mucopolysaccharidosis: clinical and biochemical aspects of leucocyte transfusion as compared with plasma infusion in patients with Hurler's and Scheie's syndromes. The therapeutic effectiveness of leucocyte transfusion (LT) was compared with that of plasma infusion (PI) clinically by range of motion (ROM) of joints and biochemically from the standpoint of alpha-L-iduronidase activity and urinary excretion of acid mucopolysaccharides (AMPS) in 2 patients with Hurler's and Scheie's syndromes. Both syndromes are considered to be due to the lack of alpha-L-iduronidase activity, a congenital metabolic disorder. As a result, leukocyte transfusion surpasses plasma infusion with respect to enzyme content, the grade and duration of clinical improvement in the stiffness of joints. Clinical improvement in the stiffness of joints was correlated with the degradation of AMPS when the ratio of urinary AMPS fragments to the total large molecule AMPS has become 50% or more after the leucocyte transfusion and plasma infusion. ( info) |
8/138. Mucopolysaccharidosis in a domestic short-haired cat--a disease distinct from that seen in the Siamese cat. A 10-month-old male domestic short-haired cat was examined because of progressive lameness, a broad face with depressed nasal bridge, small ears, corneal clouding, and multiple bone dysplasia. The cat excreted excessive amounts of glycosaminoglycan (a component of connective tissue) in its urine and had evidence of lysosomal storage of glycosaminoglycans in fibroblasts and neurons. Activity of alpha-L-iduronidase, a lysosomal enzyme involved in glycosaminoglycan degradation, was deficient in cultured fibroblasts and leukocytes. The mucopolysaccharidosis was distinct from that seen in Siamese cats in terms of the pathologic changes and the specific enzyme deficiency. ( info) |
9/138. Clinical experience in anesthetic management for children with mucopolysaccharidoses: Report of ten cases. The mucopolysaccharidoses (MPS) are hereditary disorders. Children with these disorders have multisystem disease and present significant challenges for the anesthesiologist. The establishment and maintenance of an adequate airway represents the most commonly encountered anesthesia-related problem in these patients. We report ten children with MPS who required surgical intervention. One patient died and the others had a good outcome. In this report, we share our experience and discuss the anesthetic risks and management of MPS patients. ( info) |
10/138. Dyggve-Melchior-Clausen syndrome: genetic studies and report of affected sibs. We report a brother and sister with Dyggye-Melchior-Clausen dysplasia with mental retardation (MR) but as yet without spinal cord injury due to cervical spine abnormality. Mucopolysaccharide metabolism was studied in several ways and was found to be normal. Segregation analysis and study of consanguinity data confirm that both forms of the syndrome--that with MR, and that without MR (Smith-McCort dysplasia) are rare autosomal recessives. spinal cord injury and early death is a danger in both. ( info) |