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An Exceptional Case of a Supra-tentorial Streptococcus Salivarius Brain Abscess-A Case Report
Abderrahim Bourial1,2, Wahib Lahlou2, Mounir Rghioui3
1Department of Oto-Laryngology, Cheikh Khalifa International University Hospital, Mohammed VI University of Sciences and Health (UM6SS), Casablanca, Morocco.
Introduction:
During the COVID-19 pandemic, incidence of brain abscesses is difficult to assess. Numerous studies reported benign and severe post SARS-CoV-2 vaccine side effects, including rare cases of brain abscesses associated with COVID-19 or Anti-SARS-CoV-2 vaccines. Here in, we report what we believe to be, up to date, the fourth known case in the medical literature of a streptococcus salivarius brain abscess, the first intra parenchymatous or supra-tentorial streptococcus salivarius brain abscess and also the first that occurs following an anti-SARS-CoV-2 vaccine.
Case Presentation:
We describe the case of a north african 63-year-old man with an unremarkable medical history except for recent anti-SARS-CoV-2 vaccinations. Following the administration of a third anti-SARS-CoV-2 booster vaccine, the patient developed neurological symptoms, including left hemiparesis, facial palsy, vertigo, and balance issues. Imaging studies revealed a right temporo-parietal lesion consistent with intracranial suppuration. Stereotaxic cerebral biopsy confirmed the presence of purulent content, indicating a brain abscess caused by multi-sensitive streptococcus salivarius.
Conclusion:
Sepsis-induced immunodepression appears to be a consequence of severe inflammatory state, as it dysregulates leukocytes population and results in serious infections. A plausible hypothesis is that a previous stress such as anti-SARS-CoV-2 vaccination could lead to the development of a streptococcus salivarius septicemia. In light of the available evidence and research findings, no definitive conclusion can be drawn regarding any potential link between anti-SARS-CoV-2 vaccines and the physiopathology of sepsis-induced immunodepression.
Insights
This study reports the fourth known case of a Streptococcus salivarius brain abscess, the first intra-parenchymal one, and the first following an anti-SARS-CoV-2 vaccine. This rare brain abscess case highlights potential vaccine side effects.
Area of Science:
- Neurology
- Infectious Diseases
- Vaccinology
Background:
- Assessing brain abscess incidence during the COVID-19 pandemic is challenging.
- Rare cases of brain abscesses have been linked to COVID-19 infection and anti-SARS-CoV-2 vaccines.
- Streptococcus salivarius is an uncommon cause of brain abscesses.
Observation:
- A 63-year-old man developed neurological symptoms after receiving a third anti-SARS-CoV-2 vaccine dose.
- Symptoms included left hemiparesis, facial palsy, vertigo, and balance issues.
- Brain imaging revealed a right temporo-parietal lesion, and biopsy confirmed a Streptococcus salivarius brain abscess.
Findings:
- This is the fourth reported case of a Streptococcus salivarius brain abscess globally.
- It is the first reported intra-parenchymal and supra-tentorial Streptococcus salivarius brain abscess.
- This case represents the first instance of such an abscess occurring after anti-SARS-CoV-2 vaccination.
Implications:
- The case highlights a rare potential side effect of anti-SARS-CoV-2 vaccines.
- Further research is needed to understand the potential link between vaccination and sepsis-induced immunodepression.
- This finding contributes to the understanding of rare neurological complications post-vaccination.

