EC Clinical and Medical Case Reports

Mucopolysaccharidosis type VII or Sly disease is a lysosomal storage disease, autosomal recessive, due to an enzymatic deficiency of ß-glucuronidase, responsible for the intra-lysosomal tissue accumulation of glycosaminoglycans. It is a serious disease with a very heterogeneous clinical spectrum. We describe the first Moroccan case of MPS VII in a 9-year-old child, in whom the diagnosis of MPS VII was suspected given a history of recurrent infections, a dysmorphic syndrome, macrocrania, an inguinal hernia, and a growth and cognitive delay. The diagnosis was confirmed on the increased urinary excretion of glycosaminoglycan and on the study of the enzymatic activity of ß-glucuronidase in leukocytes which was collapsed to 0.1 μmol/l/h. in the absence of enzyme replacement therapy in our context, the treatment was only symptomatic.

 Keywords: Beta-glucuronidase; Enzyme Replacement Therapy; Glycosaminoglycans; Sly's Disease; Mucopolysaccharidosis VII

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