Can we rely on the combination of serological tests and frozen sections at the time of reimplantation for two-stage exchange hip arthroplasty in patients with a \u201cdry tap\u201d?

Chi Xu,Wei Chai,Ji-Ying Chen

doi:10.1186/s13018-019-1223-9

Abstract

PurposeThe optimal timing of reimplantation of two-stage exchange arthroplasty for periprosthetic joint infection remains unknown. The purpose of the study was to (1) evaluate performance of combination of serum erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and frozen section in predicting persistent infection at the time of second-stage hip reimplantation and (2) compare accuracies of 5 and 10 polymorphonuclear neutrophils (PMNs) per high power field (HPF) as the threshold of frozen section.MethodsWe retrospectively reviewed 97 two-stage exchange hip arthroplasties from 2012–2016. Persistent infection at time of reimplantation was diagnosed using the Musculoskeletal Infection Society (MSIS) criteria. Two diagnostic models were developed. Model 1 utilized ESR, CRP, and > 5 PMNs/HPF on frozen section. Model 2 utilized ESR, CRP, and > 10 PMNs/HPF. Receiver operating characteristic (ROC) curves of the two models were generated, and areas under the curves (AUCs) were compared. A set of sensitivity analysis, using the Delphi-based consensus criteria for treatment success, was conducted to verify the accuracy of our models.ResultsThe overall rate of infection at reimplantation was 14.4%. AUCs for models 1 and 2 were 0.709 (95% confidence interval [CI], 0.557–0.852) and 0.697 (95% CI, 0.529–0.847), respectively. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 57.1%, 88.0%, 44.4%, and 92.4%, respectively, in model 1 and 42.9%, 96.4%, 66.7%, and 90.9%, respectively, in model 2. Models 1 and 2 had no significant difference in predictive values (p = 0.821). Results remained robust in the sensitivity analysis.ConclusionsThis study reveals that the combination of serum ESR, CRP, and frozen section has limited diagnostic value in predicting persistent infection at reimplantation. Additionally, no significant difference in accuracies between 5 and 10 PMNs/HPF as the threshold of frozen section were found. There is a need for timely biomarkers with higher accuracy in diagnosing infection before reimplantation.

Highlights

IntroductionTwo-stage exchange arthroplasty including spacer insertion followed by reimplantation of new implants remains the preferred method for treatment of chronic periprosthetic joint infection (PJI) in North America [1]
The management of periprosthetic joint infection (PJI) is challenging
The intraoperative decision-making process frequently has to rely on the combination of serological tests, such as serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and frozen section analysis

Summary

Introduction

Two-stage exchange arthroplasty including spacer insertion followed by reimplantation of new implants remains the preferred method for treatment of chronic PJI in North America [1]. One key reason is the lack of a “gold standard” diagnostic method indicating the infection eradiation at the time of reimplantation [5, 6]. During the second-stage procedure, the intraoperative decision of reimplantation of new prostheses or another antibiotic spacer exchange is mainly based on the combination of serological tests, aspiration analysis, and frozen section histology. The intraoperative decision-making process frequently has to rely on the combination of serological tests, such as serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and frozen section analysis

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