{
  "abstract": "Parvimonas micra (P. micra), an anaerobic oral coccus long dismissed as a culture contaminant, is increasingly recognized as a causative agent of pyogenic central nervous system (CNS) infections, yet its neuropathogenesis remains poorly defined. This narrative review synthesizes 41 peer-reviewed studies identified via a structured comprehensive literature search of PubMed, Embase and Web of Science through June 2026. Epidemiologically, pooling available case reports and small series (n=64 confirmed CNS cases), P. micra is among the most frequently isolated Gram-positive anaerobic cocci in reported brain abscess series, with proportions ranging from approximately 4% to over 10% in individual cohorts; species-level data are inconsistently reported and a precise pooled estimate cannot be derived. A male predominance (approximately 2.7:1) is observed among reported cases, though this should be interpreted cautiously given the small sample size and potential reporting bias. Approximately two-thirds of patients have no documented immunosuppressive condition. Brain abscess represents ~80% of CNS manifestations, with 60-70% presenting as polymicrobial infection. We propose a five-step pathogenic cascade-periodontal dysbiosis, epithelial barrier breach, intravascular survival, blood-brain barrier (BBB) translocation, and intracranial suppuration-as a conceptual framework. Virulence factors including the TmpC-AppA axis and extracellular vesicle DnaK have been characterized in non-CNS models (oral carcinoma, periodontitis, oral lichen planus); their relevance to CNS infection is inferred, and BBB translocation mechanisms remain entirely hypothetical. Metagenomic next-generation sequencing (mNGS) outperforms conventional culture in selected brain abscess cohorts (~85% vs ~50% in pus; ~84% vs ~8% in CSF across CNS infections), though performance varies by specimen type, prior antibiotic exposure, and sequencing platform. All-cause mortality is 5-10% and 20-25% of survivors sustain neurological sequelae, though these estimates may overestimate true population rates due to publication bias. P. micra shows consistently low in vitro minimum inhibitory concentrations to metronidazole and β-lactams. Early empirical anaerobic coverage and consideration of mNGS as a complementary diagnostic tool are recommended for suspected odontogenic brain abscess.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Infectious Diseases, Yantaishan Hospital, Yantai, Shandong, China."
  ],
  "article_type": "review article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Cancan Gong"
    },
    {
      "affs": [
        0
      ],
      "name": "Xubo Jing"
    },
    {
      "affs": [
        0
      ],
      "name": "Shanwei Jiang"
    },
    {
      "affs": [
        0
      ],
      "name": "Chaoxiao Yu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2v697a32y1c74.bib",
  "cited_by": 0,
  "doi": "10.3389/fcimb.2026.1971569",
  "fulltext_url": "https://europepmc.org/articles/PMC13678490",
  "id": "2v697a32y1c74",
  "issns": [
    "2235-2988"
  ],
  "landing_url": "https://europepmc.org/article/MED/42898979",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2746|Infectious Diseases and Tuberculosis"
    ]
  ],
  "openalex": "W7220444003",
  "pdf_url": "https://europepmc.org/articles/PMC13678490?pdf=render",
  "pmcid": "PMC13678490",
  "pmid": "42898979",
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2v697a32y1c74.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:37Z",
      "native_id": "MED:42898979",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42898979"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2746|Infectious Diseases and Tuberculosis",
      "subfield": "surgery"
    }
  ],
  "title": "Parvimonas micra and central nervous system infections: mechanisms of transformation from oral commensal to intracranial pathogen and clinical evidence.",
  "title_text": "Parvimonas micra and central nervous system infections: mechanisms of transformation from oral commensal to intracranial pathogen and clinical evidence.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:19:37Z",
  "url": "https://research.draconitic.com/paper/2v697a32y1c74",
  "venue": "Frontiers in cellular and infection microbiology",
  "versions": []
}