1/23. In-utero diagnosis of mucopolysaccharidosis type VII in a fetus with an enlarged nuchal translucency. Mucopolysaccharidosis type VII was diagnosed prenatally during the first pregnancy of a Turkish consanguineous couple, following diagnostic work-up of an increased nuchal translucency detected by ultrasound at 13 weeks of gestation. Mucopolysaccharidosis type VII (MPS VII) or Sly syndrome is a rare autosomal recessive lysosomal storage disease, caused by the deficiency of the enzyme beta-glucuronidase. The most severe form of MPS VII manifests itself by non-immune fetal hydrops. Tests for the diagnosis of metabolic disorders, especially lysosomal diseases, are essential when the major causes of hydrops fetalis have been excluded. The presence of a beta-glucosidase deficiency, Gaucher's disease, in the infant of the patient's sister emphasizes the importance of a complete family history in consanguineous couples and the risk for several recessive diseases in some families. ( info) |
2/23. Mutational analysis in longest known survivor of mucopolysaccharidosis type VII. mucopolysaccharidosis vii (MPS VII) is an autosomal recessive disorder caused by the deficiency of beta-glucuronidase leading to the intralysosomal storage of heparan, dermatan, and chondroitin sulfate. Here, we report the identification of two novel missense mutations K350N and R577L in a 37-year-old patient with beta-glucuronidase deficiency and a relatively mild MPS VII phenotype. Expression of the K350N mutation in baby hamster kidney cells has revealed residual enzymatic activity and normal transport of the enzyme to the lysosome. However, expression of the R577L or the double mutant K350N/R577L results in rapid degradation of the enzyme in early biosynthetic compartments and a total loss of enzymatic activity. We attribute the mild phenotype to the residual catalytic activity provided by the K350N mutant. At the time of her death at the age of 37 years, this patient was the longest known survivor with MPS VII. ( info) |
3/23. Mucopolysaccharidosis Type VII presenting with isolated neonatal ascites. Mucopolysaccharidosis Type VII (MPS VII) is a lysosomal storage disease caused by a deficiency of the enzyme, beta-glucuronidase. MPS VII has a wide variation in phenotypic expression, including presentation in the neonatal period with nonimmune hydrops fetalis. We report a neonate with MPS VII who initially presented with marked isolated ascites not associated with hydrops fetalis. This appears to be a novel finding in patients with MPS VII. ( info) |
| We report on fetal hydrops presenting at 18 weeks of gestation and diagnosed as beta-glucuronidase deficiency. The parents were first cousins and there were 2 previous similar fetal deaths. beta-glucuronidase was absent in cultured fetal fibroblasts and lymphoblasts but was normal in the tested relatives. The activities of other lysosomal enzymes were normal. ( info) |
5/23. Mucopolysaccharidosis type VII (beta-glucuronidase deficiency): a chronic variant with an oligosymptomatic severe skeletal dysplasia. We report on a 20-year-old male with a beta-glucuronidase (GUSB) deficiency mucopolysaccharidosis. He had pectus carinatum, gross thoracic kyphoscoliosis, and hip dysplasia, a picture which became conspicuous after age 4 years. Hepatosplenomegaly, herniae, corneal clouding, and neurological abnormalities were absent. Although he had Alder-type granulations in his polymorphonuclear leukocytes, the urine did not contain a significant excess of mucopolysaccharides. Electron microscopic examination of skin and gingival biopsies, leukocytes, and cultured skin fibroblasts showed numerous single membrane-limited vacuoles either empty or filled with fibrillogranular material; this last tissue did not contain metachromatic granules. Radiographs demonstrated a distinct spondyloepiphyseal dysplasia in which the most striking changes were confined to the thoracic spine (flattening and collapse in T7, T8 and T10 vertebral bodies) and to the femoral capital epiphyses (irregularities and fragmentation). The activity of GUSB in the patient's serum, leukocytes, and fibroblasts was severely decreased; the GUSB activity in the serum and leukocytes from the parents and 2 asymptomatic sibs was subnormal. Immunoblot analysis showed very low levels of cross-reactive material towards anti-GUSB antiserum in the patient's leukocyte and fibroblast extracts. This patient was more severely affected in his skeleton than other described patients with an oligosymptomatic chronic form. This case broadens the clinical and biochemical picture associated with GUSB deficiency and may represent a new variant of the disease. ( info) |
6/23. Mucopolysaccharidosis type VII as a cause of recurrent non-immune hydrops fetalis. BACKGROUND: Mucopolysaccharidosis type VII (MPS VII) is a rare lysosomal storage disease first described by Sly in 1973. There are fewer than thirty reported cases world wide. This extremely rare disorder can present in-utero as hydrops fetalis and has a high recurrence rate. However, prenatal diagnosis in the absence of a previously affected child, has not been reported to date. CASE: This is a case of a non-consanguineous couple, with no history of a previously affected child with MPS VII, presenting with recurrent hydrops fetalis. During the work-up, the affected fetus was diagnosed in-utero with beta-glucuronidase deficiency which is pathognomonic for MPS VII. prenatal diagnosis was then performed in subsequent pregnancies. CONCLUSION: The importance of an extensive and thorough investigation for the etiology of hydrops fetalis is discussed. ( info) |
7/23. Craniovertebral instability with spinal cord compression in a 17-month-old boy with Sly syndrome (mucopolysaccharidosis type VII): a surgical dilemma. STUDY DESIGN: A case study with review of surgical technique in craniovertebral stabilization for young children with mucopolysaccharidosis. OBJECTIVES: To describe an interesting patient with a rare metabolic disorder and review surgical technique for craniovertebral instability in this rare patient population. SUMMARY OF BACKGROUND DATA: Craniovertebral instability has been reported in patients with mucopolysaccharidosis and poses a problem for spinal surgery because of the inherent metabolic disorder and age at presentation. We present the first case of craniovertebral instability and spinal cord compression occurring in Sly syndrome (mucopolysaccharidosis type VII) who is the youngest patient afflicted with this metabolic disorder to undergo craniovertebral stabilization. methods: A 17-month-old boy presented with inability to support his head, decreasing muscle strength in all extremities, distended abdomen, and shortness of breath. The patient was found to have a dilated cardiomyopathy, hepatosplenomegaly, abnormal hepatobiliary function, corneal clouding, and a questionable tracheal anomaly. genetic testing provided a diagnosis of Sly syndrome, mucopolysaccharidosis type VII. magnetic resonance imaging revealed focal stenosis with significant spinal cord compression at the craniovertebral junction. neurologic examination revealed normal muscle volume with strength 3/5 in all extremities and significant weakness in the neck muscles with instability at the craniovertebral junction. RESULTS: On a concerted preoperative medical clearance by pediatric intensive care, pediatric neuroanesthesia, pediatric cardiology, pediatric gastroenterology, and pediatric neurosurgery, the patient underwent occipital to C3 decompression and fusion with autogenous rib grafts. The patient was placed in a prefitted halo-vest after surgery and was neurologically intact. CONCLUSIONS: This case demonstrates the heterogeneity of cervical spine deformities among the mucopolysaccharidosis syndromes and confirms the propensity for deposition of glycosaminoglycans at the craniovertebral junction. Further studies should investigate the etiology for this propensity of glycosaminoglycan deposition at the craniovertebral junction. We think that this case demonstrates that, with appropriate preoperative planning, these patients can undergo successful posterior cervical arthrodesis despite their age or metabolic defects. ( info) |
8/23. Collection of a mobilized peripheral blood apheresis product from a patient with mucopolysaccharidosis type VII and subsequent CD34 cell isolation. The effectiveness of bone marrow transplantation for lysosomal storage diseases like mucopolysaccharidosis type VII (MPSVII) suggests that a gene therapy strategy targeting autologous hematopoietic progenitor cells could be successful. Given the severe systemic manifestations of MPSVII including storage disease in the bone and bone marrow, it was unclear whether sufficient numbers of hematopoietic progenitor cells (CD34 ) could be mobilized into the peripheral circulation and subsequently purified from these patients. As reported here, G-CSF mobilization and apheresis were successful, providing a product of 4 x 10(10) nucleated cells containing 0.3% CD34 progenitors. CD34 cells were magnetically separated from the product to a final purity of 85% with a 64% yield. These results indicate that hematopoietic progenitors can safely be gathered from an MPSVII patient in numbers sufficient for the trial of clinical gene therapy applications. ( info) |
9/23. Coarctation of the thoraco-abdominal aorta associated with mucopolysaccharidosis VII in a child. Herein we describe a case of atypical coarctation of the thoraco-abdominal aorta associated with mucopolysaccharidosis vii in a 4-year-old girl. aortography showed diffuse narrowing of the descending aorta. An extra-anatomic bypass was constructed using an 8-mm Dacron graft (Meadox Medicals Inc, Oakland, NJ) between the proximal and distal portion of the descending aorta. Balloon angioplasty was necessary to treat stenoses in the infrarenal abdominal aorta. Two years postoperatively at age 6, aortography revealed no stenosis at the anastomotic sites or in the prosthesis, but the hypoplastic segment of the descending aorta between the anstomoses was completely occluded. ( info) |
10/23. beta-glucuronidase deficiency as a cause of fetal hydrops. Mucopolysaccharidosis type VII (MPS VII) was diagnosed in a case of severe fetal hydrops. beta-glucuronidase deficiency was demonstrated in the amniotic fluid, which was obtained at 25 weeks of gestation, and in the fibroblasts of the child, which were cultured after fetal death in the 26th week of gestation. In the amniotic fluid the two-dimensional electrophoresis pattern of glycosaminoglycans was in agreement with MPS VII. Based on these results, prenatal diagnosis could be offered to the couple for the next pregnancy. ( info) |