ABSTRACT
BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to be a global issue. While immunizations comprise an important line of defense, adverse effects may occur. We report two cases of autoimmune conditions affecting the nervous system, anti-N-Methyl-D-Aspartate-receptor (NMDAR) encephalitis and myasthenia gravis (MG), that developed in close association with COVID-19 vaccination. CASE REPORT: In our first case, a 29-year-old woman presents with recurrent seizures, auditory hallucinations, psychiatric symptoms, and autonomic abnormalities, with an onset of 1 day after receiving the second dose of inactivated SARS-CoV-2 whole virus vaccine. CSF analysis and electroencephalogram (EEG) were consistent with anti-NMDAR encephalitis. In our second case, a 23-year-old woman presents with ocular ptosis, diplopia, hoarseness, and fatigability, which first appeared 1-day after her first dose of inactivated SARS-CoV-2 whole virus vaccine. Electromyography (EMG) results established a definite diagnosis of MG. CONCLUSION(S): To the best of our knowledge, this is the first report of anti-NMDAR encephalitis and MG associated with inactivated SARS-CoV-2 whole virus vaccine. In both cases, COVID-19 vaccination appears to be the only remarkable feature of history. The authors postulate that COVID-19 vaccination may trigger underlying defects or induce failure of positive and negative selection, which may lead to autoreactivity and subsequent autoimmunity. However, further studies are required to confirm this possibility. Copyright © 2022, Scientific Foundation SPIROSKI. All rights reserved.