{
  "abstract": "Introduction\n\nTitanium is widely regarded as a highly biocompatible material and is extensively used in surgical implants. Nevertheless, delayed hypersensitivity reactions are increasingly recognized and may act as potential contributing factors to implant-related complications. Thoracic manifestations remain exceptionally rare, and their impact on clinical decision-making is poorly described.Case description\n\nA 65-year-old man, with chronic obstructive pulmonary disease (COPD), a 60 pack-year smoking history (former smoker since 2005) and severe gas transfer impairment, underwent video-assisted thoracoscopic right lower lobectomy for lung adenocarcinoma. The postoperative course was complicated by a prolonged air leak requiring surgical staple reinforcement and talc pleurodesis. Approximately 2 months after surgery, the patient developed invasive pneumococcal disease with Streptococcus pneumoniae bacteremia, which resolved following appropriate antimicrobial therapy. Several months later, the patient developed a bronchopleural fistula (BPF) with endobronchial extrusion of titanium staples, confirmed by computed tomography and bronchoscopy. Given the unusual presentation, allergy evaluation was performed. Patch testing demonstrated epicutaneous sensitization with positive reactions to titanium (IV) oxalate hydrate, cobalt (II) chloride hexahydrate, and manganese chloride. The allergy work-up had a direct therapeutic impact. Endoscopic closure with an Amplatzer device, a procedure documented for central BPFs, was initially considered but deliberately avoided because the considered device contains nitinol (a nickel-titanium alloy), which would expose the sensitized patient to additional titanium. Owing to the high surgical risk, conservative multidisciplinary management with close clinical and radiological surveillance was adopted.Discussion\n\nBPF is a recognized complication after lung resection and is inherently multifactorial. In this patient, established surgical, anatomical (right lower lobectomy), and patient-related comorbidity risk factors coexisted with documented titanium sensitization, suggesting that hypersensitivity may have acted as a potential contributing or modulating factor to impaired tissue integration and staple extrusion. This case highlights the diagnostic challenges of titanium hypersensitivity and the distinction between cutaneous sensitization and operative tissue allergy. Importantly, it illustrates how allergy assessment may directly influence therapeutic decision-making by avoiding further exposure to potentially allergenic metallic devices. Titanium hypersensitivity should therefore be considered as an incremental factor in selected patients with unexplained implant-related complications, even when conventional risk factors are present.",
  "abstract_shown": true,
  "affiliations": [
    "Allergy and Clinical Immunology Department Coimbra University Hospitals Local Health Unit of Coimbra Coimbra Portugal huc.min-saude.pt.",
    "Institute of Immunology Faculty of Medicine University of Coimbra Coimbra Portugal uc.pt.",
    "Center for Innovative Biomedicine and Biotechnology (CIBB) Faculty of Medicine University of Coimbra Coimbra Portugal uc.pt.",
    "UBIAir-Clinical and Experimental Lung Center and CICS-UBI Health Sciences Research Cente University of Beira Interior Covilhã Portugal ubi.pt."
  ],
  "article_type": "case study",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Mariana Lucena",
      "orcid": "0000-0003-0000-2607"
    },
    {
      "affs": [
        0
      ],
      "name": "Sara Regalo",
      "orcid": "0000-0003-3214-4140"
    },
    {
      "affs": [
        0
      ],
      "name": "Leonor Manso Preto",
      "orcid": "0000-0001-6217-4901"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Ana Todo Bom",
      "orcid": "0000-0002-1850-6689"
    },
    {
      "affs": [
        0,
        1,
        2,
        3
      ],
      "name": "Frederico Regateiro",
      "orcid": "0000-0002-6332-3056"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/a3fec9h34v6vq.bib",
  "cited_by": 0,
  "doi": "10.1155/crpu/1050765",
  "fulltext_url": "https://europepmc.org/articles/PMC13712446",
  "id": "a3fec9h34v6vq",
  "issns": [
    "2090-6846",
    "2090-6854"
  ],
  "landing_url": "https://europepmc.org/article/MED/42948770",
  "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": [
    [
      "heading",
      "Article"
    ],
    [
      "heading",
      "Case Report"
    ],
    [
      "openalex",
      "2740|Pleural and Pulmonary Diseases"
    ]
  ],
  "openalex": "W7223936838",
  "pdf_url": "https://europepmc.org/articles/PMC13712446?pdf=render",
  "pmcid": "PMC13712446",
  "pmid": "42948770",
  "published": "2026-10-27",
  "publisher": "Wiley",
  "ris": "https://research.draconitic.com/paper/a3fec9h34v6vq.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T00:20:33Z",
      "native_id": "MED:42948770",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42948770"
    },
    {
      "first_seen": "2026-10-31T12:23:00Z",
      "native_id": "PMC13712446",
      "source": "pmc",
      "url": "https://doi.org/10.1155/crpu/1050765"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2740|Pleural and Pulmonary Diseases",
      "subfield": "general"
    }
  ],
  "title": "Titanium Hypersensitivity as a Potential Contributor to Bronchopleural Fistula and Surgical Staple Extrusion Following Lung Cancer Surgery: A Case Report.",
  "title_text": "Titanium Hypersensitivity as a Potential Contributor to Bronchopleural Fistula and Surgical Staple Extrusion Following Lung Cancer Surgery: A Case Report.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T12:23:00Z",
  "url": "https://research.draconitic.com/paper/a3fec9h34v6vq",
  "venue": "Case reports in pulmonology",
  "versions": []
}