Contents lists available at ScienceDirect Parkinsonism and Related Disorders journal homepage: www.elsevier.com/locate/parkreldis Relapsing encephalopathy with dancing eyes and jerky limbs Nor Amelia Mohd Fauzi a , Suhailah Abdullah b , Ai Huey Tan b,c , Norlisah Mohd Ramli d , Cheng Yin Tan b , Shen-Yang Lim b,c,* a Department of Medicine, Faculty of Medicine, Universiti Teknologi MARA Sungai Buloh Campus, Selangor, Malaysia b Division of Neurology, Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia c The Mah Pooi Soo and Tan Chin Nam Centre for Parkinson’s and Related Disorders, University of Malaya, Kuala Lumpur, Malaysia d Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia ARTICLE INFO Keywords: Opsoclonus Myoclonus Ataxia Hashimoto's encephalopathy Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT) ABSTRACT We report a case of relapsing-remitting opsoclonus-myoclonus-ataxia syndrome (OMAS) in a patient with Hashimoto's encephalopathy, diagnosed after comprehensive evaluation. OMAS as a manifestation of Hashimoto's encephalopathy has been reported once previously. It is hoped that recognition of this entity and early initiation of immunotherapy will improve clinical outcomes for patients. A 50-year-old Indian woman presented with a four-month history of unsteadiness, reduced speech and jerky movements, worsening over two weeks. She had a background history of two steroid-responsive neurological episodes, characterized by tremor and incoordination, and bilateral leg weakness, thirteen and two years prior, respectively. She was managed in outside hospitals and recovered fully with no long-term immunotherapy. On examination, she was febrile and obtunded. There were in- voluntary, chaotic, rapid and multi-directional conjugate saccadic eye movements associated with stimulus-sensitive, brief, shock-like in- voluntary movements in the upper limbs, consistent with opsoclonus and myoclonus, respectively (Video Segment 1). She was subsequently intubated because of respiratory distress and reduced conscious state. Laboratory evaluations revealed pancytopenia and elevated liver en- zymes as complications of sepsis secondary to pneumonia. Brain MRI showed lesions in cortical and subcortical regions, pons and midbrain (Fig. 1). Electroencephalogram (EEG) demonstrated diffuse slowing without epileptiform discharges. Investigations for other sources of infectious, autoimmune and neoplastic disorders were negative (Supplementary Table). The opsoclonus-myoclonus-ataxia syndrome (OMAS) was presumed to be parainfectious in origin. She recovered over three months with empirical antibiotics without receiving im- munotherapy. Supplementary video related to this article can be found at https:// doi.org/10.1016/j.parkreldis.2019.02.025. She remained well until three years later when she represented with opsoclonus, myoclonus and emotional lability, preceded by a two- month history of irritability and gait instability. She was confused and fearful, with opsoclonus and stimulus-sensitive myoclonus in both upper limbs (Video Segment 2). Brain MRI demonstrated similar lesions as before, but without contrast enhancement. Brain MR angiogram and spinal MRI were normal. Cerebrospinal fluid (CSF) examination re- vealed mild lymphocytic pleocytosis and intrathecal IgG synthesis with oligoclonal band. EEG was diffusely slow. Surface electromyography of limb muscles showed irregular, short electromyographic bursts of 100–200 ms, consistent with myoclonus. Additional tests were per- formed during this admission. Anti-thyroid peroxidase (TPO) antibody was significantly elevated (632IU/mL) with normal anti-thyroglobulin (TG) antibody titer (28.5IU/mL). Thyroid-stimulating hormone was low with normal free T3 and T4, indicating subclinical hyperthyroidism. Extensive evaluations for infectious, autoimmune and neoplastic dis- orders were unrevealing (Supplementary Table). The patient was diagnosed with Hashimoto's encephalopathy (HE) according to the Graus criteria [1] and treated with intravenous me- thylprednisolone (1 g/day for five days), resulting in improvement of her mental state, opsoclonus and myoclonus; the EEG normalized and anti-TPO antibody titer reduced substantially (181IU/mL). However, as the patient remained emotionally labile with ataxic gait four weeks post-treatment, plasmapheresis was administered over five days. This resulted in resolution of the opsoclonus and myoclonus, and she became more conversant and started to ambulate. Anti-TPO antibody titer further reduced to 47.7IU/mL. Brain MRI three weeks after https://doi.org/10.1016/j.parkreldis.2019.02.025 Received 18 October 2018; Received in revised form 17 February 2019; Accepted 18 February 2019 * Corresponding author. Neurology Laboratory, 6th Floor, South Tower, University of Malaya Medical Centre, 50603, Kuala Lumpur, Malaysia. E-mail address: limshenyang@gmail.com (S.-Y. Lim). Parkinsonism and Related Disorders xxx (xxxx) xxx–xxx 1353-8020/ © 2019 Elsevier Ltd. All rights reserved. Please cite this article as: Nor Amelia Mohd Fauzi, et al., Parkinsonism and Related Disorders, https://doi.org/10.1016/j.parkreldis.2019.02.025