Nitrous oxide-induced toxic leukoencephalopathy

Abstract

Toxic leukoencephalopathy (TL) is characterised by an insult to the myelin of the cerebral white manner which can be attributed to a number of offending agents, including drugs of abuse. We report a case of a fit and well young man presenting to hospital with an altered mental state. It was subsequently determined that the patient inhaled a significant volume of nitrous oxide recreationally. Nitrous oxide is easily accessible and the second most consumed drug among young adolescents (16-24 years old). Following extensive investigations and brain imaging, the patient was subsequently diagnosed with TL. After a prolonged hospital admission, he went on to make a complete neurological recovery.

Keywords: drug interactions; drug misuse (including addiction); drugs misuse (including addiction); poisoning; unwanted effects/adverse reactions.

Figure 1

Axial FLAIR (A) and axial T2-weighted images (B) demonstrate a high signal in the splenium of the corpus callosum. The lesion shows restricted diffusion, that is, high signal on the axial diffusion-weighted image (C) and low signal on the corresponding apparent diffusion coefficient map images (D).

Figure 2

Follow-up MRI images after 4 months show complete resolution of the lesion in the splenium of the corpus callosum on axial T2-weighted images (A). Extensive patchy T2 hyperintensities are noted in the deep and subcortical white matter (B) and likely to represent cerebral vascular disease in the context of illicit drug use.