We report a 7-year-old female with Rasmussen Encephalitis (RE) who presented with painful left foot drop that progressed within a few weeks to painless left hemiparesis months before the onset of refractory focal seizures.

RE typically presents with progressive intractable focal seizures with subsequent deteriorating neurological deficits from unilateral cerebral inflammation.^1,2

Case Report.

A previously healthy 7-year-old female athlete initially presented with left foot pain and left ankle weakness that progressed to left foot drop within 4 weeks, which impaired her ability to walk and engage in sporting activities. Examination revealed left-sided weakness, sensory deficits, hyperreflexia, clonus, and Babinski sign on the left. Initial brain MRI (MRI-B) revealed punctate foci of T2 hyperintensity in the right periventricular white matter. Two months later, the patient returned with staring episodes, left arm stiffening, and memory impairment. Long-term EEG monitoring (LTM) captured multiple focal seizures arising from the right fronto-central region, and repeat imaging demonstrated progressive development of signal abnormality with volume loss in the right hemisphere. RE was suspected, and the patient was started on IVIg and two anti-seizure medications (ASM). She continued to have breakthrough episodes with resultant epilepsia partialis continua (EPC) captured on LTM. Repeat MRI-B revealed a significant interval increase in abnormal signals with interval evolution of volume loss in the right cerebral hemisphere. The patient underwent right hemispherectomy the following month. Post-operatively, she clinically improved and became seizure-free on three ASMs with no new neurological deficits and improvement in motor function with physical and occupational therapy.  

While RE usually presents with frequent seizures before hemiparesis, previous work by Bien, et al. has demonstrated cases of slowly progressive hemiparesis with prolonged or indefinite seizure onset delay^3,4. Our unique case demonstrates rapid-onset hemiparesis preceding seizure onset by only 3 months, followed by a refractory course ultimately leading to hemispherectomy.