Rituximab Therapy in a Patient with Recurrent Hashimoto's Encephalitis (HE), and Progressive Encephalomyelitis with Rigidity and Myoclonus (PERM) (P04.164)

Abstract

Objective: To report the results of therapy with Rituximab in a patient with recurrent HE, and PERM. Background HE is a rare autoimmune disease with recurrent neurologic and psychiatric features. PERM is a rare disorder characterized by muscular rigidity, painful spasms, myoclonus associated with autoantibodies to glutamic acid decarboxylase (GAD), glycine and NMDA receptors Design/Methods: Case report. Results: A 59-year old Caucasian woman developed new-onset generalized seizures. EEG monitoring showed bilateral focal temporal and occipital spikes with secondary generalization . Initial neurological examination, metabolic profile, brain MRI, lumbar puncture, were normal except for high anti-thyroglobulin antibodies (444 IU/ml) and anti-thyroperoxidase antibodies (55 IU/ml). Despite treatment with daily Prednisone (60 mg) and sequential addition of multiple anti-epileptic drugs (levetiracetam, topiramate, phenytoin, lacosamide and gabapentin), she had recurrent seizures and multiple admissions for status epilepticus. She received IV methylprednisone for five days without benefit. IVIg 2 gm/Kg was given twice at 1-month intervals with some improvement in the seizures for about one week. However, she relapsed and became confused, disoriented, agitated with visual hallucinations, appendicular rigidity and myoclonus and tested positive for anti-GAD antibody at 3.4 U/ml (normal 0-1.5U/ml). At this stage she was given IV Rituximab, 375 mg/m², twice at 1-week interval. There was marked improvement in cognition, rigidity and myoclonus and she was seizure-free after two cycles of Rituximab therapy. The anti-GAD antibody became undetectable. There were no immediate adverse effects from the therapy. Conclusions: Rituximab is a safe and effective treatment for HE and PERM associated with anti-GAD antibody when refractory to other immunomodulatory therapies. Disclosure: Dr. Kassar has nothing to disclose. Dr. Damodaram has nothing to disclose. Dr. Iyadurai has nothing to disclose. Dr. Chand has received personal compensation for activites with Teva Neuroscience and Allergan, Inc. as a speaker. Dr. Chand has received research support for the ANDANTE Study.