Long Pentraxin 3 as a New Biomarker for Diagnosis of Hip and Knee Periprosthetic Joint Infections

Mattia Loppini; Marco Di Maio; Roberta Avigni; Roberto Leone; Antonio Inforzato; Guido Grappiolo; Alberto Mantovani; Barbara Bottazzi

doi:10.3390/jcm12031055

Long Pentraxin 3 as a New Biomarker for Diagnosis of Hip and Knee Periprosthetic Joint Infections

J Clin Med. 2023 Jan 29;12(3):1055. doi: 10.3390/jcm12031055.

Authors

Mattia Loppini^{1

2

3}, Marco Di Maio¹, Roberta Avigni¹, Roberto Leone¹, Antonio Inforzato^{1

2}, Guido Grappiolo^{1

3}, Alberto Mantovani^{1

2

4}, Barbara Bottazzi¹

Affiliations

¹ IRCCS Humanitas Research Hospital, Rozzano, 20089 Milan, Italy.
² Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, 20090 Milan, Italy.
³ Fondazione Livio Sciutto Onlus, Campus Savona, Università degli Studi di Genova, 17100 Savona, Italy.
⁴ Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.

Abstract

Background: Preoperative diagnosis of periprosthetic joint infections (PJIs) poses an unmet clinical challenge. The long pentraxin PTX3 is a component of the innate immune system involved in infection immunity. This study evaluated the potential of synovial and plasmatic PTX3 in the diagnosis of hip and knee PJIs.

Methods: Consecutive total hip and knee arthroplasty (THA/TKA) revisions were prospectively included and classified as septic or aseptic according to the European Bone and Joint Infection Society (EBJIS) and Musculoskeletal Infection Society (MSIS) criteria. The concentration of PTX3 in plasma and synovial fluid samples was measured with ELISA. The AUC, threshold value, sensitivity, specificity, and positive and negative likelihood ratios were calculated using the ROC (receiver operating characteristic) curve method.

Results: The study population included 128 patients (94 THAs; 34 TKAs). The AUC of the synovial PTX3 based on EBJIS criteria was 0.85 (p < 0.0001), with a sensitivity of 81.13% and a specificity of 93.33%. The AUC based on MSIS criteria was 0.95 (p < 0.001), with a sensitivity of 91.43% and a specificity of 89.25%. Plasmatic PTX3 failed to discriminate infected from non-infected patients.

Conclusions: Synovial PTX3 demonstrated an excellent diagnostic potential in hip and knee PJIs, with a very high specificity irrespective of the diagnostic criteria for PJI.

Keywords: biomarkers; hip; knee; pentraxin 3; periprosthetic joint infections.

Grants and funding

This research received no external funding. We gratefully acknowledge the contribution of the European Research Council (ERC n° 669415) to A.M. and Fondazione Beppe & Nuccy Angiolini to A.I. and A.M.