Acute necrotizing encephalopathy

Abstract

Acute necrotizing encephalopathy is an extremely rare disease outside East Asia and only ten patients have been described so far. Rapid neurologic deterioration, seizures and coma occur after viral illness. We present a 8 month old patient with ANE from Croatia. A female infant developed dramatic neurologic symptoms in the pre-eruption stage of exanthema subitum. On the fourth day of illness, after which the temperature normalized, maculopapular rash of exanthema subitum appeared on the trunk, neck, face and extremities. Elevated titers of imunoglobulin M and imunoglobulin G antibodies to HHV-6 were found. The diagnosis was confirmed by magnetic resonance images. Apparent diffusion coefficient image revealed a specific „tricolor pattern“, slightly high signal in the center of the thalamic lesion, low signal in the surrounding thalamus, and high signal in the peripheral white matter. The patient was treated with acyclovir, high-dose corticosteroids and intravenous immunoglobulin, which resulted in gradual improvement of the symptoms and signs but the patient never attained her premorbid neurologic function. Early diagnosis and appropriate treatment may lead to better neurologic outcomes. The hallmark of this encephalopathy is multifocal, symmetric brain lesion, which can be visualized by magnetic resonance imaging.