Delayed post-hypoxic leukoencephalopathy (DPHL) is an underrecognized syndrome of delayed demyelination, where patients manifest neuropsychiatric symptoms after a period of 2–40 days of apparent recovery from a cerebral hypo-oxygenation episode.

We report a case of a patient who successfully recovered from an overdose of heroin, but then suffered a delayed abrupt neurological deterioration.

To improve assessment and recognition of DPHL.

An adequate retrospective collection of clinical data and nonsystematic review of the literature was performed.

A 43-year-old male with schizoaffective disorder who attempted suicide with an overdose of heroin, was successfully revived and return to his previously mental status, but 3 weeks after, he abruptly developed progressive cognitive impairment with akinetic mutism and ataxia. He was admitted to our acute psychiatric unit after brain CT and chemistry analyses were unremarkable. Brain MRI showed diffusely symmetric hyperintensity in the white matter (WM), pronominally the periventricular WM, on FLAIR and T2 weighted sequences. At 16 weeks postoverdose, he presented improvement both cognitive and motor symptoms, lasting deficits in frontal-executive functions.

DPHL is characterized by similar clinical and neuroimaging features regardless of the initial insult. The mean lucid interval coincides with the replacement half-life for myelin related lipids and proteins. Prolonged mild-to-moderate hypo-oxygenation of WM is thought to disrupt myelin turnover. It appears probable that these were responsible for DPHL in our patient rather than a direct toxicity.

DPHL can be diagnosed when clinical history, laboratory assessments and MRI findings are concordant. DPHL requires extensive support care and carries a relatively good prognosis.

The authors have not supplied their declaration of competing interest.