{
  "abstract": "Neisseria meningitidis is a notifiable pathogen in Japan when isolated from any sterile site. We describe a rare case of primary meningococcal arthritis without meningitis or bacteremia. A 48-year-old man presented with acute septic arthritis of his knee. A synovial fluid analysis using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry revealed gram-negative diplococci, identified as N. meningitidis. Further antimicrobial susceptibility testing showed the isolate was pan-susceptible, allowing de-escalation from ceftriaxone to ampicillin therapy. The patient recovered fully after surgical drainage and 4 weeks of antibiotic therapy. This case highlights the importance of considering invasive meningococcal disease upon the detection of gram-negative diplococci in synovial fluid.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "name": "Takahiro Maruyama"
    },
    {
      "name": "Takahiro Yonemoto"
    },
    {
      "name": "Haruki Imura"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/d2mky5bws4m09.bib",
  "cited_by": 0,
  "doi": "10.2169/internalmedicine.7610-26",
  "fulltext_url": "https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7610-26/_article",
  "id": "d2mky5bws4m09",
  "issns": [
    "1349-7235",
    "0918-2918"
  ],
  "landing_url": "https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7610-26/_article",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "jstage-journal",
      "medicine/general"
    ],
    [
      "openalex",
      "2404|Bacterial Infections and Vaccines"
    ]
  ],
  "openalex": "W7221828179",
  "pdf_url": "https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7610-26/_pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/d2mky5bws4m09.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:31Z",
      "native_id": "10.2169/internalmedicine.7610-26",
      "source": "jstage",
      "url": "https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7610-26/_article"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "openalex:2404|Bacterial Infections and Vaccines",
      "subfield": "microbiology"
    }
  ],
  "title": "Septic Arthritis of the Knee Caused by Neisseria meningitidis Serogroup Y",
  "title_text": "Septic Arthritis of the Knee Caused by Neisseria meningitidis Serogroup Y",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:31Z",
  "url": "https://research.draconitic.com/paper/d2mky5bws4m09",
  "venue": "Internal Medicine",
  "versions": []
}