Abstract
We report a case of adult-onset adrenoleukodystrophy. A 35-year-old right-handed man was admitted with impairments of auditory and visual acuity. Family history was negative for neurologic and psychiatric disorders. He had clear consciousness and good orientation. Neurologic examination showed left-dominant auditory disturbance which was proven by audiometry to be of the retrocochlear type. Although he had a partial visual field defect in the right eye, his visual acuity was 0.5 (right) and 0.4 (left) with normal color perception. Motor and cerebellar function were normal. Deep tendon reflexes were hyperactive together with positive Babinski signs. The sensory system was normal except for impaired skin writing tests and tactile extinction phenomenon on the left side. However, psychometric evaluation could be carried out without any trouble. Understanding of spoken and written language was normal on the Standard Language Test for Aphasia. However, some impairments in recognition of word accents and spatial direction of sound sources were observed. Regarding comprehension of non-verbal sounds, he was unable to identify familiar, meaningful nonverbal environmental sounds (e. g., ringing bell). These findings supported the diagnosis that he had auditory agnosia without aphasia.
T2-weighted MRIs of the brain showed diffuse high signal intensities in the deep white matter of the occipito-temporo-parietal lobe. Laboratory tests disclosed high plasma concentration of very long chain fatty acid. Cerebrospinal fluid protein was elevated. In conclusion, the present case was thought to have auditory agnosia with a mechanism involving transcortical fibers due to adrenoleu-kodystrophy.
