Toxic leucoencephalopathy after 'chasing the dragon'.

Toxic leucoencephalopathy (TLE) is a rare neurological complication of heroin abuse. 'Chasing the dragon' is an inhalational mode of heroin abuse that originated in Southeast Asia. Intriguingly, no cases of TLE have been reported from this region, although the inhalational mode of heroin abuse is common. We herein report the case of a middle-aged man with a history of polysubstance abuse who presented with progressive neurological symptoms and progressed to an uncommunicative state. While the initial impression was that of iatrogenic parkinsonism, diffuse leucoencephalopathy with sparing of the cerebellum was noted on magnetic resonance imaging. In view of his history of inhalational heroin abuse close to the onset of the neurological symptoms, a diagnosis of TLE was made. No clinical improvement was noted with administration of a dopaminergic agent. This is the first known case of delayed TLE following heroin inhalation from Southeast Asia with the unusual feature of cerebellar sparing.