Identify patients who had breakthrough seizures following COVID-19 vaccine administration.  

Neurologic complications occur following vaccinations. The coronavirus (COVID-19) vaccines are also associated with neurological side effects. For example, 100 cases of Guillian Barre Syndrome were reported following 12.5 million doses of the Johnson & Johnson vaccine. Five case reports of thrombosis and thrombocytopenia, with corresponding cerebral venous sinus thrombosis (CVST) were reported with the Johnson & Johnson vaccine. Lastly, a recent study noted that out of 54 patients with epilepsy, one patient had increased seizure frequency following vaccination and another patient had a new seizure semiology. The impact of the COVID-19 vaccines on primary brain tumor patients is unknown.    

We analyzed the 866 patients at the Alvord Brain Tumor Center from January 2021 to April 2021. We describe here 15 patients with primary brain tumors who experienced breakthrough seizures within a week of receiving the first or second dose of the Moderna or Pfizer vaccines.   

Sixty percent of patients had glioblastoma, the median age of 60 years, with males and females relatively equally affected (47% vs. 53%). Approximately 70% were not on active treatment at the time of seizure breakthrough. The last episode of seizure was at least six months prior to the seizure breakthrough in 33% of patients. Seizures occurred a median of one day after the most recent vaccine. Seizure breakthrough reports were similar between first and second vaccine doses (47% vs. 53%). In two patients, seizure following their COVID-19 vaccine was the first manifestation of their primary brain tumor.   

COVID-19 vaccines may lower seizure threshold by systemic inflammation or sleep disruption. Given the likely increased risks of COVID-19 infection among patients with brain tumors, vaccination is still recommended. Patient counseling on sleep hygiene, fever, and strict adherence to seizure medication is crucial to mitigate the risk of seizure post-vaccination.