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Post-coronavirus inflammatory cerebral peduncle lesion presenting as painful tonic spasms
Jin Kyung Kim1, Robert de Santis2, Rachelle Dugue2
1Neurology, Stanford University, Stanford, California, USA kimjk@stanford.edu.
Abstract:
Painful tonic spasms (PTS) are paroxysmal, stereotyped, painful episodes of involuntary posturing typically associated with demyelinating or structural lesions within the corticospinal tract. We report a case of PTS in temporal association with a COVID-19 infection, most likely attributable to post-infectious neuroinflammation. A woman in her 40s developed frequent, disabling, painful spasms of the left extremities 2 weeks after a COVID-19 infection. An MRI of the brain revealed a solitary contrast-enhancing T2/fluid-attenuated inversion recovery hyperintense ovoid lesion in the right cerebral peduncle. Comprehensive cerebrospinal fluid and serum evaluation, including demyelinating and autoimmune panels, was unremarkable. A 24-hour electroencephalogram capturing three episodes showed no electrographic abnormalities. Symptoms resolved following a short course of high-dose intravenous methylprednisolone and long-term oxcarbazepine. Serial imaging over 2 years demonstrated an interval decrease in lesion size and complete resolution of contrast enhancement, most consistent with a monophasic post-infectious inflammatory aetiology.
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