Fucosidosis – I. Clinical and Enzymological Studies

Three new cases of fucosidosis are described. The symptomatology of two patients started in the first year of life. Firstly a delay of psychomotor development was noted. Then hypotonia developed. Both children, brother and sister, suffered from frequent respiratory infections. The hypotonia of the eldest patient changed gradually into severe spasticity and ultimately into decerebrate rigidity.

Both patients had coarse facial features, resembling those of the mucopolysaccharidoses.

Hepatomegaly existed in both children. Angiokeratoma corporis diffusum did not occur in this pedigree. Radiological examination of the skull revealed severe sclerosis and hyperostosis of the base of the skull. X-rays of the vertebral column revealed the same abnormalities of the vertebrae as seen in the mucopolysaccharidoses.

Electronmicroscopy of N. suralis and liver biopsy showed storage material, some of which had a very regular lamellar structure. The activity of α-L-fucosidase in the leucocyte was deficient.

The enzyme activity of the parents was in the heterozygote range.

The clinical expression of the third patient was totally different.

The age of onset was 7²/₁₂; years. The disease started with focal neurological symptoms: left sided myoclonus and a left sided hemiparesis.

In the course of a year a gradual regression of mental capacities and motor skills became evident.

There were no features resembling to mucopolysaccharidoses, nor radiological abnormalities.

Enzymological investigations showed deficiency of the activities of α-L-fucosidase and arylsulfatase A.

The reduction of the α-L-fucosidase was however less than in the “classical” cases.

It is suggested, that the combined reduction of both enzyme activities is a condition for the clinical expression of the disease and for its late onset as well.

Fucosidosis