Mild Encephalopathy With Reversible Splenial Lesion Related to Antiepileptic Drugs: Report of 3 Cases (P5.101)

OBJECTIVE: The rare syndromic condition of mild encephalitis/encephalopathy with reversible lesion in the callosal splenium (MERS) within the spectrum of transient and reversible diffusion weighted imaging and attenuation of diffusion coefficient map signal changes seen in the splenium of corpus callosum (SCC). Antiepileptic drugs (AED) feature prominently among the many etiological associations reported for this condition. We report three cases one from three different age demographic, with clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) BACKGROUND: The first patient is a 34 year-old female with intractable generalized epilepsy being treated with five AEDs in addition to vagal nerve stimulation. She presented with altered acute personality changes, followed by altered awareness. Her history suggested inadvertent discontinuation of her AEDs. The second patient was a 58 year-old female who was on high doses of carbamazepine for low back ache who recently reduced the dose herself and presented with acute personality changes. The 3rd patient is a 70 year-old male presenting with acute onset of myoclonic jerks and personality changes after acute contrast nephropathy while on Levetiracetam DESIGN/METHODS: Clinical exam and MRI were performed. Additional tests including lumbar punctures and blood work up were also performed. Electroencephalogram (EEG) was performed in all 3. Followup MRI also were done RESULTS: All of their MRIs showed diffusion restricted signal changes in the SCC. Lumbar punctures revealed mild elevation of protein but otherwise unremarkable for signs of infection. EEGs showed sharp transients that reversed on follow up within a span of days. Followup MRIs also revealed resolution of SCC lesions CONCLUSIONS: MERS is often a benign condition, whose MRI characteristics in combination with historical and clinical points help make the diagnosis. Symptomatic management would be sufficient as patients clinically improve rapidly and without sequelae. Study Supported by: N/A Disclosure: Dr. Rajan has nothing to disclose. Dr. King has nothing to disclose. Dr. Uppal has nothing to disclose. Dr. Vellipuram has nothing to disclose. Dr. Singh has nothing to disclose.