Asterixis associated with anatomic cerebral lesions: a study of 45 cases.

Introduction: Asterixis is an uncommon sign in structural central nervous system disorders. When asterixis is present, one cannot rule out the possibility of a focal lesion, but it is almost always due to a metabolic encephalopathy.

Patients And Methods: In the last five years all patients with uni- or bilateral neurologic asterixis attended in our hospital have been studied. Cerebral computed tomogram or magnetic resonance imaging was performed in all patients with uni or bilateral asterixis.

Results: We describe 45 patients with different forms of structural cerebral pathology who presented unilateral (37 patients) or bilateral (8 patients) asterixis not associated to either toxic or metabolic disorder. Central nervous system ischemic or hemorrhagic disorders were found to be the most frequent causes of asterixis (95.5%) and the thalamus the most frequent localization for unilateral asterixis to result (54%).

Conclusions: Bilateral asterixis is not always associated with toxic or metabolic disorders and it may be a sign of some structural neurologic alterations. A good correlation was found between the presence of unilateral asterixis and structural intracranial disease.