title: MRI gadolinium enhancement precedes neuroradiological findings in acute necrotizing encephalopathy.
abstract: We report a 2-year-old Japanese boy with acute necrotizing encephalopathy (ANE) triggered by human herpes virus-6, who presented insightful magnetic resonance imaging (MRI) findings. He was admitted due to impaired consciousness and a convulsion, 2 days after the onset of an upper respiratory infection. At admission, cranial MRI showed marked gadolinium enhancement at the bilateral thalami, brainstem and periventricular white matter without abnormal findings in noncontrast MRI sequences. On the following day, noncontrast computed tomography demonstrated homogeneous low-density lesions in the bilateral thalami and severe diffuse brain edema. The patient progressively deteriorated and died on the 18th day of admission. The pathogenesis of ANE remains mostly unknown, but it has been suggested that hypercytokinemia may play a major role. Overproduced cytokines cause vascular endothelial damage and alter the permeability of the vessel wall in the multiple organs, including the brain. The MRI findings in our case demonstrate that blood-brain barrier permeability was altered prior to the appearance of typical neuroradiological findings. This suggests that alteration of blood-brain barrier permeability is the first step in the development of the brain lesions in ANE, and supports the proposed mechanism whereby hypercytokinemia causes necrotic brain lesions. This is the first report demonstrating MRI gadolinium enhancement antecedent to typical neuroradiological findings in ANE.
authors.affiliation: Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan. Electronic address: tyoshida10@gmail.com.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Takuya
authors.initials: T
authors.lastname: Tamura
authors.forename: Yuhki
authors.initials: Y
authors.lastname: Nagai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ueda
authors.forename: Tomonari
authors.initials: T
authors.lastname: Awaya
authors.forename: Minoru
authors.initials: M
authors.lastname: Shibata
authors.forename: Takeo
authors.initials: T
authors.lastname: Kato
authors.forename: Toshio
authors.initials: T
authors.lastname: Heike
mesh_terms: D044466:Asian People; D001921:Brain / Q000473:pathology*; D002675:Child, Preschool; D003287:Contrast Media; D018792:Encephalitis, Viral / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D005682:Gadolinium; D015654:Herpesvirus 6, Human; D006801:Humans; D004684:Leukoencephalitis, Acute Hemorrhagic / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D011859:Radiography
chemical_list: D003287:Contrast Media; D005682:Gadolinium