Mimic of transient ischemic attack by anemia-induced asterixis: A novel differential diagnosis of stroke with critical pitfalls.

ABSTRACT

As most cases of asterixis with metabolic causes are asymptomatic, they have not been considered in the differential diagnosis of stroke. However, an asterixis occasionally resembles a transient ischemic attack (TIA). On the other hand, reports have indicated that anemia is an independent risk factor for brain ischemia. Therefore, both asterixis and anemia are important considerations for stroke diagnosis. A 79-year-old man with frequent leg palsy was initially diagnosed with recurrent TIA at the anterior cerebral artery (ACA) with a tiny callosal infarction and aspirin was prescribed immediately. However, subsequent careful physical examination revealed asterixis at both the wrist and knee joints. Laboratory testing and colonoscopy revealed severe anemia secondary to colon cancer. Blood transfusion immediately improved the asterixis and gait, thus confirming that anemia contributed to the patient's symptoms. This novel etiology of asterixis may be accompanied by misleading anemia-induced brain ischemic lesions detectable on magnetic resonance imaging (MRI). Anemia-induced asterixis should be considered as a novel differential diagnosis of a stroke to avoid pitfalls leading to unnecessary stroke treatment for patients with anemia.