Rinsho Shinkeigaku (Clinical Neurology)

Case Report

Delayed posthypoxic leukoencephalopathy: Case reports

Shiho Okuda, M.D., Ph.D.1), Masao Ueno, M.D.1), Michiko Hayakawa, M.D., Ph.D.2), Manabu Araki, M.D., Ph.D.3), Fumio Kanda, M.D., Ph.D.4) and Shin Takano, M.D., Ph.D.1)

1)Department of Neurology, Hyogo Rehabilitation Center Hospital
2)Department of Internal Medicine, Hyogo Rehabilitation Center Hospital
3)National Center Hospital, National Center of Neurology and Psychiatry
4)Department of Neurology, Kobe University Hospital

Delayed posthypoxic leukoencephalopathy (DPL) is a rare and less well known complication of hypoxic brain injury. Although it is well known that anoxic or hypoxic injury produces acute neurologic deficits, DPL typically manifests days to weeks after apparent recovery from an obtunded state, and patients with DPL demonstrate cognitive impairment, high brain dysfunction, parkinsonism, or psychosis. MRI findings of the brain demonstrate deep white matter abnormalities. We report 2 cases of DPL after hypoxia due to benzodiazepine overdose. Both of our patients had normal arylsulfatase A activity. Although DPL is seen in carbon monoxide poisoning, pseudodeficiency of arylsulfatase A activity, or drug overdose with heroin or morphine, there are only some previous studies of DPL caused by an overdose with benzodiazepine. It is unclear whether neurotoxicity from the drug in addition to hypoxia alone is involved, however, it is important to note that overdose of common drugs as sleeping medicine can cause DPL. Since DPL may often be misdiagnosed and be subjected to unnecessary treatments, it is also important to understand its unique clinical course and MRI findings. With prompt recognition of DPL, we expect that more cases of DPL caused by overdose with benzodiazepine will be diagnosed, because benzodiazepine overdoses are common.
Full Text of this Article in Japanese PDF (442K)

(CLINICA NEUROL, 52: 672|676, 2012)
key words: Delayed posthypoxic leukoencephalopathy, Overdose with benzodiazepine, Normal arylsulfatase A activity

(Received: 3-Apr-12)