Infiltration of tissues with oligosaccharides and glycoproteins results in vomiting, hepatosplenomegaly, large head, thick calvaria, low anterior hairline, coarse facial features (Hurler-like), thick eyebrows, flat nose, large ears, macroglossia, widely spaced teeth, gingival hypertrophy deafness, lens opacities, prognathism, tall stature, ataxia, and muscular hypotonia. Other clinical features include lumbar gibbus, big hands and feet, dysostosis multiplex, bowed femurs, storage cells in bone marrow, vacuolated lymphocytes, pancytopenia, recurrent respiratory tract infections, immunoglobulin deficiency, hypogammaglobulinemia, antiplatelet antibodies, antineutrophil antibodies, low haptoglobin level, and severe mental retardation (adult form). Pectus carinatum, skeletal abnormalities, dilated cerebral ventricles and raised intracranial pressure, spondylolysis and spondylolisthesis of L5 on S1.