Adult-onset metachromatic leukodystrophy presenting as isolated peripheral neuropathy

A 38-year-old man presented with weakness of the lower limbs. Electrophysiology revealed a pronounced demyelinating neuropathy. Nerve biopsy disclosed de- and remyelinating lesions and characteristic lamellar inclusions in Schwann cells and macrophages. There was no familial history of neurologic disorder, and impairment of motor evoked potentials was the only sign of CNS involvement. Arylsulfatase A and cerebroside sulfate sulfatase activities in leukocytes and cultures of the patient's fibroblasts were low. The sulfatide loading test also revealed abnormal sulfatide accumulation. This may be the first reported case of adult metachromatic leukodystrophy presenting as peripheral neuropathy.