Alpha-mannosidosis type I. Infantile variety. Alpha-d-mannosidase deficiency.
Incidence
This conditon is inherited autosomal recessive. Approximately seventy patients have been reported or probably much more cases than these for types I and II.
Clinical Characteristics
This form is more severe than type II, there is mental retardation and the clinical deterioration is severe, facial dysmorphism, dysostosis multiplex and hepatomegaly are obvious. Patients have susceptibility to infection. Deafness, lenticular and corneal opacities, hepatomegaly and repeated respiratory infections are other prominent part of the disorder. Clinical characteristics: There is vomiting and slight hepatosplenomegaly. On the face, there is a large head, thick calvaria, low anterior hairline, coarse features, thick eyebrows, flat nose, large ears, macroglosia, wider spaced teeth, gingival hypertrophy, deafness, lens opacities, prognatism. These patients tend to have a tall stature. There is muscular hypotonia. In the skeletal changes are lumbar gibus, big hands and feet, dysostosis multiplex and bowed femurs. Hematologically there is storage cell in bone marrow, vacuolated lymphocytes and pancitopenia. There is recurrent respiratory tract infection, immunoglubulin deficiency, hipogammaglobulinemia, antiplatelets antibodies, antineutrophil antibodies, low haptoglobin levels. There is mental retardation, pectus charinatum. There are skeletal abnormalities with dilated cerebral ventricles, spondylolisis and spondylolistesis of L5 on S1. The course of the disease is brief with death occuring usually between three and ten years of age. Laboratory shows deficiency of alpha-d-mannosidase, other acid hydrolases higher than normal and mannose-rich oligosacchariduria.
Precipitants
no
Provocation Tests
no
Diagnostic Procedures
EB-W, EB-F. Laboratory shows deficiency of alpha-d-mannosidase, other acid hydrolases higher than normal and mannose-rich oligosacchariduria. There is storage cells in bone marrow, vacuolated lymphocytes and pancitopenia. A large amount of mannose-rich oligosaccharides are excreted in the urine.