An interventional study of Synovial Alpha-defensin assay and Synovial Neutrophil elastase assay in Joint Infection, Infection of Hip Joint (Disorder) and Infection of Shoulder Joint, sponsored by Hospital for Special Surgery, New York. Recruiting at 3 sites in United States. Open to participants aged Up to 17 Years. Per ClinicalTrials.gov, last updated 2026-07-29.
Sponsored by Hospital for Special Surgery, New York · Not applicable, Interventional, and Diagnostic
Differentiating between septic arthritis and other causes of joint inflammation in pediatric patients is challenging and of the utmost importance because septic arthritis requires surgical debridement as part of the treatment regimen. The current gold standard to diagnose septic arthritis in children is a positive synovial fluid culture; however, joint cultures may take several days to return. If a bacterial infection is present, it requires immediate surgical intervention in order to prevent lasting articular cartilage damage. Frequently surgeons must decide whether to surgically debride a joint before culture results are available. There is no single lab test or clinical feature that reliably indicates bacterial infection over other causes of joint inflammation. The alpha-defensin assay has shown high sensitivity and specificity for joint infection in other studies.The purpose of this study is to determine the sensitivity and specificity of several synovial biomarkers for diagnosing pediatric septic arthritis.
The purpose of this study is to determine if alpha-defensin and other proteins present in joint fluid may be able to rapidly diagnose bacterial joint infections. Patients with suspected joint infection typically undergo joint aspiration so that tests can be performed to help diagnose joint infection, including gram stain, cell count, and culture. Patients under 18 years old that are undergoing sampling of their joint fluid due to suspicion of infection or inflammation will be enrolled in this multi-center trial. Joint fluid will also be sampled from normative controls made up of patients who are undergoing an unrelated procedure without inflammation or infection. Joint fluid from patients with suspected inflammation/infection and from normative controls will be analysed for presence of alpha-defensin, leukocyte esterase, neutrophil elastase, synovial C-reactive protein, and synovial lactate. The alpha-defensin assay has shown high sensitivity and specificity for joint infection in other studies. Additionally a Staphylococcus spp antigen panel, Candida spp antigen panel, Enterococcus faecalis assay, BACTAlert culture, cell count plus differential, gram stain, and aerobic, anaerobic, and fungal cultures will be done using synovial fluid. A synovial fluid PCR for Kingella kingae will be performed if the patient is under eight years of age. Blood tests will include cell count and differential, erythrocyte sedimentation rate, C-reactive protein, procalcitonin, and D-dimer, as well as relevant inflammatory or rheumatologic marker tests. Results from these tests will be compared to joint fluid culture which the gold standard for diagnosing bacterial infection. The study includes 1 visit per patient, the standard of care visit in which the patient would be undergoing joint aspiration or arthroscopy. Once data has been collected, the sensitivity and specificity will be determined for these experimental tests both individually and in combination.
51 studies on the registry are indexed under Arthritis, Infectious; 12 are open to participants now.
This study's planned enrollment of 442 is above the median of 41 across 21 interventional studies indexed under Arthritis, Infectious.
Browse Arthritis, Infectious studies →Hospital for Special Surgery, New York is the lead sponsor of 226 studies on the registry; 40 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 22 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria- Septic Cases and Inflamed, Non-Septic Comparators:
Inclusion Criteria- Normative Controls:
Exclusion Criteria- All Participants:
Exclusion Criteria- Normative Controls:
Patients undergoing joint aspiration/debridement due to suspicion of septic joint or rheumatologic/inflammatory condition
Diagnostic Test: Synovial Alpha-defensin assay · Diagnostic Test: Synovial Neutrophil elastase assay · Diagnostic Test: Synovial lactate assay · Diagnostic Test: Synovial C-reactive Protein (CRP) · Diagnostic Test: Synovial Staphylococcus spp antigen panel · Diagnostic Test: Synovial Candida spp antigen panel · Diagnostic Test: Synovial Enterococcus faecalis assay · Diagnostic Test: Synovial bacterial culture by BacT/Alert · Diagnostic Test: Synovial Cell count + differential (CBC) · Diagnostic Test: Synovial Gram Stain · Diagnostic Test: Synovial Leukocyte Esterase Test Strips · Diagnostic Test: Synovial PCR for Kingella kingae · Diagnostic Test: Serum Cell count + differential (CBC) · Diagnostic Test: Serum erythrocyte sedimentation rate (ESR) · Diagnostic Test: Serum C-reactive Protein (CRP) · Diagnostic Test: Serum D-dimer · Diagnostic Test: Serum Procalcitonin · Diagnostic Test: Blood Cultures · Diagnostic Test: Optional blood testing per standard of care (ASO, anti-strep, ANA, anti-DS-DNA, HLA-B27, RF, Lyme and other inflammatory/ rheumatologic markers )
Patient undergoing procedure unrelated to infection/inflammation
Diagnostic Test: Synovial Alpha-defensin assay · Diagnostic Test: Synovial Neutrophil elastase assay · Diagnostic Test: Synovial lactate assay · Diagnostic Test: Synovial C-reactive Protein (CRP) · Diagnostic Test: Synovial Staphylococcus spp antigen panel · Diagnostic Test: Synovial Candida spp antigen panel · Diagnostic Test: Synovial Enterococcus faecalis assay · Diagnostic Test: Synovial bacterial culture by BacT/Alert · Diagnostic Test: Synovial Cell count + differential (CBC) · Diagnostic Test: Synovial Gram Stain · Diagnostic Test: Synovial Leukocyte Esterase Test Strips · Diagnostic Test: Synovial PCR for Kingella kingae · Diagnostic Test: Serum Cell count + differential (CBC) · Diagnostic Test: Serum erythrocyte sedimentation rate (ESR) · Diagnostic Test: Serum C-reactive Protein (CRP) · Diagnostic Test: Serum D-dimer · Diagnostic Test: Serum Procalcitonin · Diagnostic Test: Blood Cultures · Diagnostic Test: Optional blood testing per standard of care (ASO, anti-strep, ANA, anti-DS-DNA, HLA-B27, RF, Lyme and other inflammatory/ rheumatologic markers )
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
Synovial Fluid (joint fluid) will be sent out to CD Diagnostics for this test.
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
The synovial fluid (joint fluid) sent to CD Diagnostics for testing will also be cultured to see if any organisms grow.
One of the synovial fluid (joint fluid) tests that will be performed by the outside lab, CD Diagnostics.
This will be performed by CD Diagnostics if any organisms are present in the synovial fluid.
These test strips will be tested at the hospital where the patient is being seen, a few drops of synovial fluid will be used on the strip.
In participants \< 8 years old, a sample of synovial fluid will be tested for Kingella kingae using PCR.
A blood test performed at the hospital.
A blood test performed at the hospital.
A blood test performed at the hospital.
A blood test performed at the hospital.
A blood test performed at the hospital.
Blood will be cultured at the hospital to see if any organisms grow.
In patients with suspected inflammation/infection, there are other blood tests which may be standard of care and used for diagnosis.
Sensitivity and specificity of experimental tests
Sensitivity and specificity have been selected as these are standard outcome tests when determining the utility of a diagnostic test.
Time frame: Interim analysis at 2 years of study recruitment
Plan to share: No — Collaborating sites will share de-identified patient data with the primary site, the Hospital for Special Surgery. The Hospital for Special Surgery, will incorporate de-identified aggregated data into a separate de-identified aggregated data sat to be provided to all study sites, but individual participant data will not be shared with all sites.
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