Diagnostic value of plasma fibrinogen in chronic periprosthetic infection / 中华骨科杂志

ABSTRACT

Objective:To investigate the diagnostic value of plasma fibrinogen (FIB) in chronic periprosthetic joint infection (PJI).Methods:A total of 470 patients who underwent revision hip and knee arthroplasty after primary hip and knee arthroplasty in the First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2021 were retrospectively analyzed. According to the diagnosis of the disease, 173 patients (112 hips and 61 knees) were divided into chronic PJI group, including 78 males and 96 females, aged 65 (53, 72) years; and 297 patients (216 hips and 81 knees) were divided into aseptic loosening group, including 108 males and 189 females, aged 63 (50, 72) years. The preoperative levels of FIB, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), D-dimer and platelet were compared between the two groups, and the sensitivity and specificity of the diagnosis of chronic PJI were calculated. Receiver operating characteristic (ROC) curves were used to determine the optimal cut-off values of FIB, CRP, ESR, platelet and D-dimer for the diagnosis of chronic PJI. The diagnostic efficacy of each indicator was analyzed by comparing the area under curve (AUC) and using a combined diagnostic test.Results:FIB, CRP, ESR, platelets and D-dimer in the chronic PJI group were 4.05 (3.52, 4.72) g/L, 19.5 (10.7, 40.0) mg/L, 50 (28, 60) mm/1 h, 270 (221, 351)×10 9 /L, 514 (261, 873) μg/L, respectively, which were higher than 3.25 (2.80, 3.63) g/L, 3.7 (2.0, 6.7) mg/L, 20 (12, 30) mm/1 h, 225 (182, 269)×10 9 /L, and 310 (167, 569) μg/L in sterile loosening group, with statistically significant differences ( P<0.05). The AUC of FIB, CRP, ESR, platelets and D-dimer in the diagnosis of chronic PJI were 0.78 (95% CI: 0.73, 0.82), 0.86 (95% CI: 0.82, 0.89), 0.80 (95% CI: 0.76, 0.85), 0.68 (95% CI: 0.63, 0.73), 0.64 (95% CI: 0.59, 0.69); the optimal cut-off values were 3.73 g/L, 9.64 mg/L, 39 mm/1 h, 280×10 9 /L, 624 μg/L; the sensitivity was 68%, 79%, 69%, 47%, 43%; the specificity was 81%, 85%, 85%, 81%, 79%, respectively. When CRP, ESR, FIB, platelets and D-dimer were combined sequentially to diagnose patients with chronic PJI, the sensitivity and specificity of the series test were 12.7% and 99.7%, and those of the parallel test were 100% and 37.3%. The combined diagnostic test showed that the maximum AUC of FIB combined with CRP was 0.85 (95% CI: 0.81, 0.89), with a sensitivity of 76% and a specificity of 89%. Conclusion:The clinical value of plasma FIB in the diagnosis of chronic PJI is not superior to that of CRP and ESR, but the combination of FIB and CRP can improve the specificity.