血清学指标联合关节液分析在关节感染诊断中的应用

Application of serological index combined with synovial fluid analysis in the diagnosis of joint infection

目的探讨血清CRP、ESR、D-二聚体和关节液CRP、白细胞酯酶(LE)试纸在关节感染诊断中的应用和价值。方法选取2018年8月至2020年12月在宁波市第六医院关节外科、骨内科就诊的178例患者,依据2018年肌肉与骨骼感染协会(MSIS)诊断标准更新版本判断关节是否感染,将患者分为感染组22例和非感染组156例,检测两组患者血清CRP、ESR、D-二聚体水平和关节液CRP水平,并作LE试纸测试。绘制ROC曲线分析血清CRP、ESR、D-二聚体和关节液CRP诊断关节感染的Youden指数和最佳截断值,并比较联合检测的效能。同时将LE试纸定性测试结果与MSIS诊断标准更新版本进行对比,计算LE试纸测试灵敏度、特异度、阳性预测值、阴性预测值。结果感染组ESR、关节液CRP、血清CRP水平高于非感染组(均P<0.05),感染组D-二聚体水平与非感染组的差异无统计学意义(P>0.05)。关节液CRP的最佳截断值为37.2 mmol/L,灵敏度和特异度分别为0.800和0.804,其AUC大于联合检测AUC。假体感染的LE试纸灵敏度和特异度分别为0.875和1.000,LE试纸阳性预测值和阴性预测值分别为100%和94.74%。原生关节感染的LE试纸阳性预测值明显较低,为26.32%,但LE试纸阴性预测值仍保持在96.49%。结论关节液CRP对关节感染有很好的诊断价值,其诊断价值优于血清CRP、ESR、D-二聚体,与联合检测的诊断价值差异无统计学意义。LE试验对排除原发性感染性关节炎有良好的价值。

Objective To investigate the application of serum CRP,ESR,D-dimer,synovial fluid CRP and leukocyte esterase(LE)strips in the diagnosis of joint infection.Methods A total of 178 patients admitted in the Department of Joint Surgery and Orthopedics of Ningbo Six Hospital from August 2018 to December 2020 were enrolled.According to the diagnostic criteria of Musculoskeletal Infection Association(MSIS,2018)there were 22 patients diagnosed as joint infection(infection group)and 156 patients without joint infection(non-infection group).Serum CRP,ESR,D-dimer,synovial fluid CRP and LE strips were detected in the two groups.The diagnostic value of serumand synovial fluid markers and LE strips for joint infection was analyzed by receiver operating characteristic(ROC)curve.Results The levels of ESR,synovial fluid CRP,serum CRP in the infection group were higher than those in the non-infection group(P<0.05).There was no significant difference in D-dimer between the two groups(P<0.05).The cut-off value of CRP in synovial fluid was 37.2 mmol/L,and the sensitivity and specificity were 0.800 and 0.804,respectively.The sensitivity and specificity of LE strips for prosthesis infection were 0.875 and 1.000,and the positive and negative predictive value were 100%and 94.74%respectively.The positive predictive value of LE strips for primary joint infection was significantly lower(26.32%),but the negative predictive value of LE strips remained at 96.49%.Conclusion Synovial fluid CRP have good diagnostic value for joint infection,which is better than that of serum CRP,ESR and D-dimer in serum,and no significant difference with the combined test.Leukocyte esterase strip test is good for exclusion of primary infectious arthritis.