Laboratory Value Effectiveness in Predicting Early Postoperative Periprosthetic Joint Infection After Total Hip Arthroplasty.

Abstract

BACKGROUND:

Diagnosing early periprosthetic joint infection (PJI) after primary total hip arthroplasty (THA) remains challenging. We sought to validate optimal laboratory value cutoffs for detecting early PJIs in a series of primary THAs from one institution.

METHODS:

We retrospectively identified 22,795 primary THAs performed between 2000 and 2019. Within 12 weeks, 43 hips (43 patients) underwent arthrocentesis. Patients were divided into 2 groups: evaluation ≤6 weeks or 6-12 weeks following THA. The 2011 Musculoskeletal Infection Society major criteria for PJI diagnosed PJI in 15 patients. Mann-Whitney U-tests were used to compare median laboratory values and receiver operating characteristic curve analysis was used to evaluate optimal cutoff values.

RESULTS:

Both within 6 weeks and between 6 and 12 weeks postoperatively, median C-reactive protein (CRP), erythrocyte sedimentation rate, synovial white blood cell (WBC) count, neutrophil percentage, and absolute neutrophil count (ANC) values were significantly higher in infected THAs. Optimal cutoffs within 6 weeks were: CRP ≥100 mg/L, synovial WBCs ≥4390 cells/μL, neutrophil percentage ≥74%, and ANC ≥3249 cells/μL. Between 6 and 12 weeks, optimal cutoffs were: CRP ≥33 mg/L, synovial WBCs ≥26,995 cells/μL, neutrophil percentage ≥93%, and ANC ≥25,645 cells/μL.

CONCLUSION:

Early PJI following THA should be suspected within 6 weeks with CRP ≥100 mg/L or synovial WBCs ≥4390 cells/μL. Between 6 and 12 weeks postoperatively, cutoffs of CRP ≥33 mg/L, synovial fluid WBC ≥26,995 cells/μL, and neutrophil percentage ≥93% diagnosed PJI with high accuracy.

LEVEL OF EVIDENCE:

Level IV Diagnostic.

• Authors: Evan M Dugdale, Mason E Uvodich, Douglas R Osmon, Mark W Pagnano, Daniel J Berry, Matthew P Abdel
• Journal: The Journal of arthroplasty (J Arthroplasty) Vol. 37 Issue 3 Pg. 574-580 (03 2022) ISSN: 1532-8406 [Electronic] United States
• PMID: 34774687 (Publication Type: Journal Article)
• Copyright: Copyright © 2021 Elsevier Inc. All rights reserved.

Chemical References

• Biomarkers
• C-Reactive Protein

Topics

• Arthroplasty, Replacement, Hip (adverse effects)
• Biomarkers
• Blood Sedimentation
• C-Reactive Protein (analysis)
• Humans
• Laboratories
• Prosthesis-Related Infections (diagnosis, etiology)
• Retrospective Studies
• Sensitivity and Specificity
• Synovial Fluid (chemistry)