Application of Metagenomics Sequencing in a Patient with Dementia: A New Case Report.

(1) Background: The study of the microbiome is crucial for its role in major systemic diseases, in particular the oral and gut microbiota. In recent years, the study of microorganisms correlated, for example, with neurodegenerative disease has increased the prospect of a possible link between gut microbiota and the brain. Here, we report a new case concerning a patient who was initially evaluated genetically for dementia and late-onset dyskinesia, and later tested with 16S metagenomics sequencing. (2) Methods: Starting from a buccal swab, we extracted bacterial DNA and then we performed NGS metagenomics sequencing based on the amplification of the hypervariable regions of the 16S rRNA gene in bacteria. (3) Results: The sequencing revealed the presence of the Spirochaetes phylum, a pathogenic bacterium generally known to be capable of migrating to the Central Nervous System. (4) Conclusions: Oral infections, as our results suggest, could be possible contributing factors to various neurodegenerative conditions.