A Single Source for Joint Infection Diagnosis

Diagnosing Infection with Synovasure®

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Joint infection can occur in a patient with a joint prosthesis (Periprosthetic Joint Infection, or PJI) or a patient without a prosthesis (Native Septic Arthritis, or NSA). Diagnosing joint infection can be challenging and making a comprehensive laboratory workup important to provide a complete view of the potential organism that may be the source of the potential infection.

 

At CD Laboratories, we offer comprehensive synovial fluid testing solutions to aid in the diagnosis of joint infection – Synovasure® Comprehensive PJI Panel with SynTuition® and Synovasure® Comprehensive NSA Panel – through a combination of proprietary and standard of care (SoC) tests and fulfills the 2018 International Consensus Meeting (ICM) PJI diagnosis criteria. Learn more about the criteria, click here.

Synovasure® Comprehensive Infection Panels

The Synovasure® Comprehensive PJI Panel with SynTuition® offers proprietary and standard of care (SoC) tests that are combined into a proprietary, validated machine learning algorithm providing a probability score to aid in the diagnosis of Periprosthetic Joint Infection (PJI). The panel includes:

  • Synovasure® Alpha Defensin
  • Synovial Fluid C-reactive Protein (CRP)
  • White Blood Cell (WBC) with differential

Optional Add-on: Crystal Analysis

Culture is performed alongside the Synovasure® Comprehensive PJI Panel with SynTuition®, but is not included within the score.

For additional information on tests, click here

Note: SynTuition® is available as a laboratory developed test (LDT)

The Synovasure® Comprehensive NSA Panel offers proprietary and standard of care (SoC) tests to aid in the diagnosis of Native Septic Arthritis (NSA). The panel includes:

  • Synovasure® Alpha Defensin for NSA (alpha defensin and lactate)
  • White Blood Cell (WBC) with differential
  • Culture
  • Crystal Analysis
For additional information on tests, click here

Note: All specimens are tested for specimen integrity as part of the Synovasure® Comprehensive Infection Panels

SynTuition®

SynTuition® is the first-of-its-kind machine learning algorithm-based score that combines multiple biomarker analyte test results to aid in the diagnosis of PJI through a streamlined interpretation.

Accurate1

  • High sensitivity and specificity (vs. 2018 ICM PJI definition)
  • Minimizes inconclusive diagnosis rate to 0.6%

Timely

  • Results within 24 hours of receipt at CD Laboratories

Simple

  • Easy-to-understand graphical representation of score and individual test results provided on results report
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Sensitivity1
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Specificity1

Synovasure® Alpha Defensin ELISA

Alpha defensin is an antimicrobial peptide released in response to a pathogen in synovial fluid which is used as a biomarker to aid in the diagnosis of joint infection. 

 

The Synovasure® Alpha Defensin ELISA Test is a laboratory-based test, only available from CD Laboratories, to detect elevated alpha defensin levels in synovial fluid.

Clinically Validated Performance2-6

  • High sensitivity and specificity based on 2013 MSIS criteria for PJI
  • Performance unaffected by:
    • Prior antibiotic administration
    • Comorbidities related to inflammation
    • Type and/or virulence of organism
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Sensitivity2
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Specificity2
  1. Parr J et al. Probability Score for the Diagnosis of Periprosthetic Joint Infection – Development and Validation  of a Practical Multi-analyte Machine Learning Model. Cureus. 17(5): e84055, 2025. 
  2. M40003 – Synovasure Alpha Defensin ELISA Instructions for Use (IFU), 2023.
  3. Deirmengian C., et al. Combined Measurement of Synovial Fluid a-Defensin and C-Reactive Protein Levels: Highly Accurate for Diagnosing Periprosthetic Joint Infection. Journal of Bone and Joint Surgery. 96(17):1439-45, 2014.
  4. Shahi A., et al. The Alpha-Defensin Test for Periprosthetic Joint Infection is Not Affected by Prior Antibiotic Administration. Clinical Orthopedics and Related Research. 474(7):1610-5, 2016.
  5. Miyamae Y., et al. Diagnostic Accuracy of the Alpha-Defensin Test for Periprosthetic Joint Infection in Patients with Inflammatory Diseases. Journal of Arthroplasty. 34(8):1767-1771, 2019.
  6. Deirmengian C., et al. The C-reactive Protein May Not Detect Infections Caused by Less-Virulent Organisms. Journal of Arthroplasty. 31(9 Suppl):152-155, 2016.