{
    "abstract": "This study evaluated the predictive value of Krebs von den Lungen-6 (KL-6) for the development of coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) and its association with mortality in critically ill COVID-19 patients. A retrospective single-center cohort study was conducted on critically ill COVID-19 patients who required high-flow oxygen or mechanical ventilation between January 2021 and June 2023. Serial serum KL-6 levels were measured at admission and weekly thereafter. The predictive performance of initial KL-6 was assessed using ROC curve analysis, and risk factors for CAPA and 30-day mortality were analyzed using multivariable models. Among 238 patients, 25 (10.5%) developed CAPA. Initial KL-6 demonstrated good discriminative ability for CAPA prediction (AUC 0.745; 95% CI: 0.685-0.799), with an optimal cutoff of 270.9 U/ml (sensitivity: 88.0%, specificity: 55.4%). KL-6\u00a0\u2265\u00a0270.9 U/ml remained independently associated with CAPA (aHR: 9.66; 95% CI: 2.28-40.89) after multivariable analysis. Serial measurements showed a trend toward a greater increase in KL-6 levels among CAPA patients than non-CAPA patients (median difference: 259.9 vs. 73.0 U/ml, P\u00a0=\u00a0.053). Additional independent predictors of CAPA included inotropic/vasopressor support, diabetes mellitus, and tocilizumab use. CAPA patients had higher all-cause 30-day mortality (60.8% vs. 45.2%; P\u00a0=\u00a0.020), which remained significant after adjustment (aHR: 2.19; 95% CI: 1.08-4.15). Furthermore, KL-6 was independently associated with 30-day mortality (aHR: 1.03 per 100 U/ml; 95% CI: 1.00-1.07). These findings suggest that KL-6 is a promising biomarker for predicting CAPA and mortality in critically ill COVID-19 patients.\nThis study assessed serum Krebs von den Lungen-6 (KL-6) as an indicator of coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA). Higher serum KL-6 levels and their increase over time were associated with CAPA development and mortality in critically ill COVID-19 patients.",
    "authors": [
        {
            "affiliation": "Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon-si, Republic of Korea.",
            "firstname": "Hyun Kyu",
            "initials": "HK",
            "lastname": "Cho"
        },
        {
            "affiliation": "Division of Infectious Diseases, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon-si, Republic of Korea.",
            "firstname": "Si-Ho",
            "initials": "SH",
            "lastname": "Kim"
        },
        {
            "affiliation": "Division of Infectious Diseases, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon-si, Republic of Korea.",
            "firstname": "Cheon-Hoo",
            "initials": "CH",
            "lastname": "Jeon"
        },
        {
            "affiliation": "Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon-si, Republic of Korea.",
            "firstname": "Jae Wan",
            "initials": "JW",
            "lastname": "Jung"
        },
        {
            "affiliation": "Division of Infectious Diseases, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon-si, Republic of Korea.",
            "firstname": "Yu Mi",
            "initials": "YM",
            "lastname": "Wi"
        }
    ],
    "conclusions": null,
    "copyrights": "\u00a9 The Author(s) 2025. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.\n\u00a9 The Author(s) 2025. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.",
    "doi": "10.1093/mmy/myaf032",
    "journal": "Medical mycology",
    "keywords": [
        "COVID-19",
        "KL6 antigen",
        "SARS-CoV-2",
        "aspergillosis",
        "human",
        "mortality"
    ],
    "methods": null,
    "publication_date": "2025-04-08",
    "pubmed_id": "40194943",
    "results": null,
    "title": "KL-6 as a predictor of coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) and mortality in critically ill COVID-19 patients: A single-center retrospective cohort study.",
    "xml": "<Element 'PubmedArticle' at 0x788506c34e50>"
}