The authors present the case-history of a female patient with the adult form of metachromatic leukodystrophy. Metachromatic leukodystrophy is a rare hereditary disease with an autosomal recessive heredity, its cause being deficiency of the lysozome enzyme arylsulphatase A. The patient’s disease was clinically manifested in early adult age (22 years) by change of behaviour, impaired posture and impaired gait. CT examination of the brain revealed multifocal damage of the white matter and mild cerebral atrophy. MRI examination showed dystrophic changes of the white matter of the brain. EMG examination revealed marked reduction of the conduction velocity in motor and sensory fibres. Protein in cerebrospinal fluid was not elevated. Chromatographic analysis of the urinary sediment revealed markedly increased excretion of suphatides (galactosylceramide I3 sulphate).Deficiency of arylsulphatase A activity in leucocytes confirmed the diagnosis of metachromatic leukodystrophy. DNA analysis confirmed in the arylsulphatase A gene a mutation P426L in the homozygoid form. The disease is monitored for 6 years. In the clinical neurological picture dominates at present impaired posture and gait along with disintegration of the personality.

        Key words: metachromatic leukodystrophy, adult form, arylsulphatase A