Leukoencephalopathy after inhalation of heroin vapor.

A 25-year-old man presented in March 1996 with progressive dysarthria, cerebellar ataxia, and dystonia, which began after he inhaled heroin vapor for a full day 2 months previously. The patient had a 2-year history of heroin inhalation. Magnetic brain stimulation showed waveform dysynchronization suggestive of motor pathway perturbation above the cervical spinal level. Brain computed tomography and magnetic resonance imaging revealed extensive symmetric white matter involvement of bilateral cerebral and cerebellar hemispheres and the brainstem, especially along the corticospinal tract. The clinical features, electrophysiologic manifestations, and imaging studies strongly indicated a lipophilic toxin-induced demyelinating process, mainly involving the central motor system, as the most likely cause of heroin leukoencephalopathy. This is the first reported case of heroin-related leukoencephalopathy in Taiwan.