Background Myasthenia gravis (MG) is an autoimmune disorder of the neuromuscular junction that can be exacerbated by many viral infections, including COVID-19. The management of MG exacerbations is challenging in this scenario. We report 8 cases of MG exacerbation or myasthenic crisis associated with COVID-19 and discuss prognosis and treatment based on a literature review. Results Most patients were female (7/8), with an average age of 47.1 years. Treatment was immunoglobulin (IVIG) in 3 patients, plasma exchange (PLEX) in 2 patients, and adjustment of baseline drugs in 3. In-hospital mortality was 25% and 37.5% in 2-month follow-up. Discussion This is the largest case series of MG exacerbation or myasthenic crisis due to COVID-19 to this date. Mortality was considerably higher than in myasthenic crisis of other etiologies. Previous treatment for MG or acute exacerbation treatment did not seem to interfere with prognosis, although sample size was too small to draw definitive conclusions. Further studies are needed to understand the safety and effectiveness of interventions in this setting, particularly of PLEX, IVIG, rituximab, and tocilizumab.

Myasthenia Gravis (MG) is an autoimmune disorder of the neuromuscular junction that can be exacerbated by many viral infections, including COVID19. Management of MG exacerbations is challenging in this scenario. We report 8 cases of MG exacerbation or myasthenic crisis associated with COVID19 and discuss prognosis and treatment based on a literature review. Most patients were female (7/8), with an average age of 47.1 years. Treatment was immunoglobulin (IVIG) in 3 patients, plasma exchange (PLEX) in 2 patients, and adjustment of baseline drugs in 3. In-hospital mortality was 25% and 37.5% in 2-month follow-up. This is the largest case series of MG exacerbation or myasthenic crisis due to COVID19 to this date. Mortality was considerably higher than in myasthenic crisis of other etiologies. Previous treatment for MG or acute exacerbation treatment did not seem to interfere with prognosis, although sample size was too small to draw definitive conclusions. Further studies are needed to understand the safety and effectiveness of interventions in this setting, particularly of PLEX, IVIG, rituximab and tocilizumab.

Background Anti-NMDAR encephalitis is an emerging differential diagnosis of first episode and persistent psychosis in the psychiatric community, as clinical manifestations include psychiatric symptoms, cognitive dysfunction, seizures, decreased consciousness, and dyskinesias. This disease is associated with extreme delta brush (EDB), but the significance and temporal course of this EEG pattern still needs to be determined. Herein, we report a case of anti-NMDAR encephalitis with persistent psychosis associated with EDB occurrence on multiple occasions during a 5-year disease course. Case presentation A 15-year-old girl was diagnosed with anti-NMDAR encephalitis and treated with progressive improvement. Four years after initial manifestations, an EDB pattern was seen on electroencephalogram (EEG) without new neurological symptoms. She had residual symptoms of episodic auditory hallucinations and impulsivity. One year later, the patient had a recurrence of neurological symptoms (seizures, dyskinesias and impaired attention), persisting with EDB on EEG. Clinical symptoms and EDB resolved after second-line treatment with rituximab. Conclusion We describe the first case of persistent psychosis in anti-NMDAR encephalitis associated with extreme delta brush on multiple EEGs on prolonged follow-up. Electroencephalographic patterns such as EDB may serve as markers of residual disease activity, including psychiatric symptoms. Further studies with prolonged EEG monitoring are needed to better understand these findings.