Congenital metachromatic leucodystrophy with severe and persistent muscular hypotonia [Leucodistrofia metacromatica congenita con grave e persistente ipotonia muscolare]

Described is a case of congenital metachromatic leucodystrophy with muscular hypotonia until death at the age of 4 yr. The parents, first cousins, both are heterozygotes for the disease. (Arylsulphatase A in father's leucocytes: 44.4; of the mother: 46.5 of the controls: 157.3 ± 50; and of the propositus: 9.6). The peculiarity of this congenital form is the persistence of the very severe muscular hypotonia without evolution toward the spastic quadriparesis. Discussed is the differential diagnosis with other muscular hypotonias of the first and second infancy.