A case of adult type adrenoleukodystrophy with an acute onset and repeated episodes of ataxic dysarthria

We report a 30-year-old man with adult type adrenoleukodystrophy (ALD) who manifested an acute onset and repeated episodes of ataxic dysarthria. He noticed a moderate dysarthria after a high grade fever in February of 1995; however, two weeks later his symptom disappeared completely. Three months later, he noticed the dysarthria again and he was referred to our hospital for further examination. General physical findings on admission revealed a dark skin color, pigmentation of gingivae and reduced body hair. Neurologically he was normal except for a moderate ataxic dysarthria. Cranial T2-weighted MRI showed multiple high intensity lesions in the subcortical white matter of frontal lobe, bilateral peritrigonal white matter, splenium of the corpus callosum and bilateral cerebellar white matter. Only cerebellar lesions responsible for his symptom were enhanced on MRI after gadolinium administration. Initially we diagnosed him with multiple sclerosis (MS) based upon the clinical course and MRI findings, and then started corticosteroid treatment. His dysarthria was slightly improved after the treatment and bilateral gadolinium-enhanced lesions of cerebellar white matter on MRI disappeared. Multimodality evoked potentials such as short latency somatosensory evoked potentials, brainstem auditory evoked potentials and pattern-reversal visual evoked potentials, disclosed a prolonged central conduction time associated with bilaterally symmetric individual interpeak latencies. These findings, which supported diffuse and bilateral subclinical demyelinating lesions in the central nervous system, were unusual for MS; therefore his plasma very-long-chain fatty acids (VLCFA) were assayed for ALD. Finally, he was diagnosed with adult type ALD because of the high ratio of C26: 0/C22: 0 (0.075; normal 0.033). It is very difficult to clinically distinguish the early stage of adult type ALD especially in patients like this from MS. Therefore it is useful and important to evaluate not only the level of plasma VLCFA, but also to evaluate multimodality evoked potentials.