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Evaluating a pathogen-specific IgG binding assay for rapid detection of healthcare-associated infections
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  • Published: 21 February 2026

Evaluating a pathogen-specific IgG binding assay for rapid detection of healthcare-associated infections

  • Asiye Karakullukçu1,
  • Mustafa Akker2,
  • Mert Ahmet Kuşkucu3,
  • Gökhan Aygün4 &
  • …
  • Yalım Dikmen5 

Scientific Reports , Article number:  (2026) Cite this article

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We are providing an unedited version of this manuscript to give early access to its findings. Before final publication, the manuscript will undergo further editing. Please note there may be errors present which affect the content, and all legal disclaimers apply.

Subjects

  • Adaptive immunity
  • Applied microbiology
  • Bacterial infection

Abstract

Rapid and accurate diagnosis of healthcare-associated infections (HAIs) is an unmet need for improving outcomes in intensive care units (ICUs). Traditional culture-based methods, while the gold standard, are time-consuming and can delay therapeutic interventions. In this study, we evaluated the diagnostic utility of pathogen-specific immunoglobulin G (IgG) binding levels using an enzyme-linked immunosorbent assay (ELISA). We measured IgG binding against pathogens including Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Enterococcus faecium, and Staphylococcus aureus. Diagnostic performance was evaluated through receiver operating characteristic (ROC) curve analysis, with culture results as the reference. The assay demonstrated an overall diagnostic accuracy of 83.2%, with a sensitivity of 85.4%, a specificity of 81.4%, and an area under the curve (AUC) of 0.910. Pathogen-specific cutoff values ranged from 0.918 to 1.534. Especially, A. baumannii showed the highest performance metrics, achieving a sensitivity of 94.7%, a specificity of 93.6%, and an AUC of 0.975. The pathogen-specific IgG binding levels can offer a novel and effective diagnostic tool for the initial assessment of HAIs, enhancing early detection and improving patient management across healthcare settings.

Data availability

The data that support the findings of this study are not openly available due to sensitivity reasons and are available from the corresponding author upon reasonable request. The data are stored in controlled-access storage systems by the corresponding author.

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Acknowledgements

The authors would like to thank Prof. Dr. Can Günay from Cerrahpaşa University Hospital for statistical assistance and Mürsel Baydemir from Bogazici University for helping with the acquisition of data.

Funding

This study was funded by the Turkish Scientific and Technological Research Council [Project Number: 20170294 to Asiye Karakullukçu].

Author information

Authors and Affiliations

  1. Faculty of Medicine, Department of Medical Microbiology, Istanbul Health and Technology University, Istanbul, Turkey

    Asiye Karakullukçu

  2. Department of Intensive Care, Istinye University Medical Park Gaziosmanpasa Hospital, Istanbul, Turkey

    Mustafa Akker

  3. Faculty of Medicine, Department of Medical Microbiology, Koç University, Istanbul, Turkey

    Mert Ahmet Kuşkucu

  4. Cerrahpasa Faculty of Medicine, Department of Medical Microbiology, Istanbul University-Cerrahpasa, Istanbul, Turkey

    Gökhan Aygün

  5. Cerrahpasa Faculty of Medicine, Department of Anesthesiology and Reanimation, Istanbul University-Cerrahpasa, Istanbul, Turkey

    Yalım Dikmen

Authors
  1. Asiye Karakullukçu
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Contributions

AK has full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. All authors contributed to the study’s conception and design. Material preparation and analysis were performed by AK, data collection was performed by MA, and visualization was performed by MAK. The first draft of the manuscript was written by AK. YD and GA provided critical revisions and supervision. All authors revised it critically for important intellectual content. All authors read and approved the final manuscript. All authors gave final approval for the version to be published.

Corresponding author

Correspondence to Asiye Karakullukçu.

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Karakullukçu, A., Akker, M., Kuşkucu, M.A. et al. Evaluating a pathogen-specific IgG binding assay for rapid detection of healthcare-associated infections. Sci Rep (2026). https://doi.org/10.1038/s41598-025-30459-7

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  • Received: 02 September 2024

  • Accepted: 25 November 2025

  • Published: 21 February 2026

  • DOI: https://doi.org/10.1038/s41598-025-30459-7

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Keywords

  • Healthcare-associated infections
  • Pathogen-specific IgG
  • Intensive care unit
  • Rapid diagnostic test
  • Enzyme-linked immunosorbent assay
  • Antibiotic stewardship
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