[Hemichorea in a patient with acute cerebral infarction of the somatosensory cortex].

A 86-year-old woman with left hemiparesis was admitted to our hospital. When visiting to our hospital, hemichorea appeared on her left extremities in an ambulance. She also had mild disturbance of consciousness, spatial disorientation, and sensory disturbance. Blood biochemical studies revealed mild renal failure. DWI MRI showed hyperintensities in the postcentral gyrus and a posterior part of the insula in the right hemisphere, but no signal changes in FLAIR. No lesions were detected in the basal ganglia. The DWI-FLAIR mismatch suggested acute cerebral infarction, and we performed intravenous thrombolysis therapy. Her neurological symptoms including hemichorea gradually improved, and she was finally discharged on foot. Two conspicuous points of the present patient are the sensory cortical infarction and an association with renal failure. In this patient, the sensory cortical infarction must produce chorea even though sensory cortical lesions rarely caused chorea. The associated renal dysfunction may play some role in the production of chorea. The double-crash of cerebral infarction and metabolic abnormality (renal dysfunction) may cause hemichorea which is rarely seen in patients with cerebral infarction of the sensory cortex and insula with no metabolic abnormalities.