ABSTRACT
Acute necrotizing encephalopathy is a novel disease entity, proposed by Mizuguchi et al in 1995, that shows a characteristic selective and symmetric involvement of the thalamus, brain stem, and cerebellum. It usually leaves sequelae. The etiology of acute necrotizing encephalopathy is unknown. We describe here six patients aged 6 months to 5 years (four boys and two girls). Four cases were typical, and the patients' cranial computed tomographic scans and magnetic resonance imaging showed irreversible symmetric involvement of the thalamus, brain stem, and cerebellum. Three of the patients died, and one was left with severe sequelae. In the other two patients, who had selective reversible thalamic involvement, the disease was mild; one also showed transient unilateral thalamic involvement. These patients recovered completely. We consider the illness in these two patients to fit the criteria of the mild form of acute necrotizing encephalopathy. We believe that acute necrotizing encephalopathy has some clinical diversity, as is seen in other neurologic disorders, and that a mild form could exist.
Subject(s)
Influenza A virus/isolation & purification , Leukoencephalitis, Acute Hemorrhagic/classification , Leukoencephalitis, Acute Hemorrhagic/complications , Orthomyxoviridae Infections/complications , Thalamus/pathology , Atrophy/etiology , Brain Stem/pathology , Child, Preschool , Fatal Outcome , Female , Humans , Infant , Leukoencephalitis, Acute Hemorrhagic/diagnosis , Magnetic Resonance Imaging , Male , Orthomyxoviridae Infections/diagnosis , Remission, Spontaneous , Tomography, X-Ray ComputedABSTRACT
This report describes two Spanish cases of acute necrotizing encephalopathy of childhood, a rare disease first described in Japan by Mizuguchi and colleagues. Similar cases have been reported from Taiwan and other countries of the Far East. Two cases have been reported from the UK and one from the USA. The disease affects young children and is characterized by acute encephalopathy after a viral illness, with seizures and decreased levels of consciousness. The hallmark of the disease is diffuse and symmetrical CNS lesions of both thalami, internal capsules, upper brainstem tegmentum, and cerebral white matter. The aetiology is unknown but an infectious or parainfectious process seems likely. Because of the predominant involvement of the thalami, we propose the term 'infantile bilateral thalamic necrosis', a more specific term and one which distinguishes the entity from other basal ganglia diseases in childhood.