Periodic Lateralized Epileptiform Discharges Associated With Irreversible Hyperglycemic Hemichorea-Hemiballism

Periodic lateralized epileptiform discharges (PLEDs) on electroencephlography (EEG) usually indicate an acute, diffuse, and severe cerebral insult. Although hyperglycemic hemichorea-hemiballisum (HCHB) and striatal hyperintensity on T1-weighted magnetic resonance (MR) images is an accepted clinical entity, PLEDs have not previously been reported. Herein, we report a 74-year-old man with hyperglycemic HCHB, hyperintense putamen on T1-MR images and PLEDs on EEG. Aggressive sugar control with neuroleptic treatment only slightly improved the severity of HCHB. We also tried titrated oral and intravenous haloperidol, clonazepam, and propranolol sequentially and in combination; however, the effects were poor. Unlike the generally reversibility of hyperglycemic HCHB, the condition was still present 6 months later. Hyperglycemia can cause HCHB and produce subcortical type-PLEDs, which may explain the findings in our patient. In conclusion, PLEDs can be found in patients with hyperglycemic HCHB and striatal hyperintensity on T1-weighted MR images, and the appearance of PLEDs may indicate an irreversible outcome. EEG should be considered in such circumstances.