Toxic leukoencephalopathy or toxic spongiform leukoencephalopathy is a condition that is characterized by progressive damage (-pathy), of the white matter (leuko-) of the brain (-encephalo-) due to ingested toxins (toxic).
It is seen in some people who ingest heroin by route of smoking (chasing the dragon). It is currently unknown by what means the smoking of heroin causes the condition.
Toxic leukoencephalopathy has also been reported as a consequence of cranial irradiation and chemotherapy in the treatment of leukemias, such as acute lymphoblastic leukemia.[1]
Toxic leukoencephalopathy affects white matter tracts devoted to higher cerebral function, causing clinical features that range from inattention, forgetfulness, and changes in personality to dementia, coma, and death.[2] Obvious signs of the condition are difficulty with cognitive function and equilibrioception.