Late infantile metachromatic leukodystrophy presenting with extrapyramidal sign

Abstract

Metachromatic leukodystrophy (MLD) is a progressive white matter disease caused by arylsulfatase A deficiency. Demyelination in the nervous system is detected by cerebral magnetic resonance imaging and neurophysiological studies. We present here a child with late infantile MLD, who had initially difficulties in standing and walking with generalized dystonia and clubfoot and later on became unable to stand and sit even with support. Protein levels in cerebral spinal fluid were elevated and nerve conduction studies revealed slowing down of motor and sensory nerve conduction velocity. Initial cerebral computerized tomography scan showed hypo dense lesion in bilateral globus pallidus. Magnetic resonance imaging was done subsequently that showed diffuse white matter signal changes. Enzyme assay for arylsulfatase A further confirmed the diagnosis of MLD. We conclude that in young children extrapyramidal symptomatology and demyelinating sensorimotor polyneuropathy may be a presenting feature of the onset of MLD.

Keywords

Metachromatic leukodystrophy - arylsulfatase A - neurodegenerative disorder