Case Reports in Neurological Medicine / 2019 / Article / Tab 1

Case Report

The Spectrum of Acute Disseminated Encephalomyelitis and Mild Encephalopathy with Reversible Splenial Lesion

Table 1

Diagnostic criteria for ADEM, MERS type 1 and MERS type 2.

ADEM (Krupp 2013) [4]MERS type 1MERS type 2 (Notebaert 2013) [20]

Clinical manifestations(i) A first polyfocal, clinical CNS event with presumed inflammatory demyelinating cause(i) Clinical onset associated with neuropsychiatric symptoms within 1 sweek after fever onset.
(ii) Encephalopathy that cannot be explained by fever(ii) Encephalitis or encephalopathy: speech difficulties, drowsiness, decreased consciousness, delirium, seizures, irritability, agitation, and disorientation
(iii) No new clinical and MRI findings emerge three months or more after the onset(iii) Complete recovery without sequelae, mostly within 10 days after the onset of neuropsychiatric symptoms

Brain MRI(i) Diffuse, poorly demarcated, large (>1–2 cm) lesions involving predominantly the cerebral white matter(i) High-signal-intensity lesions on T2-weighted images, isointense to hypointense lesions on T1-weighted imaged and a homogenously reduced diffusion(i) High-signal-intensity lesions on T2-weighted images, isointense to hypointense lesions on T1-weighted imaged and a homogenously reduced diffusion
(ii) T1 hypointense lesions in the white matter are rare(ii) Lesions are seen in the midline of the splenium of the corpus callosum without contrast-enhancement(ii) Lesions affect in a variable degree the corpus callosum (from its anterior aspect to its totality) and in a bilateral and symmetrical fashion the center semiovale without contrast-enhancement
(iii) Deep grey matter lesions (e.g. thalamus or basal ganglia) can be present(iii) Complete resolution of the splenial lesion on repeat imaging within 1 week, with no residual signal changes or atrophy
(iv) Gadolinium enhancement of one or more lesions occurs in 14–30% of cases(iii) Complete resolution of the splenial lesion on repeat imaging within 1 week, with no residual signal changes or atrophy
(v) In addition to findings on brain MRI, patients with ADEM can have extensive lesions on spinal MRI

ADEM = Acute disseminated encephalomyelitis, MERS = Mild encephalopathy with reversible splenial lesion, CNS = Central Nervous system, MRI = Magnetic resonance imaging.

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