CHOROIDEREMIA WITH LEUKOENCEPHALOPATHY AND ARYLSULFATASE-A PSEUDODEFICIENCY

A 33-year-old male patient was admitted to our hospital because of pro gressive gait disturbance and involuntary movement of the neck. He sho wed choroideremia, distal motor neuropathy, and leukoencephalopathy on T2-weighted brain magnetic resonance imaging (MRI), Choroideremia is a rare X-linked, progressive, degenerative disease of retina and choro id. There have been some reports of choroideremia patients with neurol ogical complications. Recent studies have assigned its genetic locus t o a small segment of Xq21.3 and it encodes a protein that resembles co mponent A of rat Rab geranyl-geranyl transferase, a protein essential for cell function. This patient did not have the reported genetic abno rmalities for choroideremia. Known disorders causing leukorncephalopat hy were not detected except for a partial deficiency of arylsulfatase A (17.3% of normal controls in lymphocytes and 13.7% in fibroblasts). Deficiency of arylsulfatase A activity occurs in the late infantile, j uvenile, and adult forms of metachromatic leukodystrophy (MLD) which i s also an inherited disorder of myelin metabolism, but because of its unstability, it occurs in normal individuals and in patients with othe r neurological diseases. Consequently, we suspect that this patient ha d partial deficiency of arylsulfatase A and choroideremia as predispos ing factors for white matter degeneration.