In this disorder the combined clinical features of late infantile metachromatic leucodystrophy (MLD) and a mucopolysaccharidosis are present. During the first or second year there is a disturbance of motor function followed by a progressive neurological regression which is usually more rapid than in MLD. Features of a mucopolysaccharidosis may appear earlier or later in the course of the disease, and include mild coarsening of the facial features, hepatosplenomegaly and lumbar kyphosis. Dysostosis multiplex is evident radiologically, resembling that seen in Hurler disease. Ichthyosis develops at 2-3 years. A severe form presenting in the neonatal period also occurs. These patients have a dysmorphic facial appearance, short neck, hepatomegaly, epiphyseal dysplasia, hydrocephalus and ichthyosis.