The serum level of D-Dimer is not suitable for distinguishing between prosthetic joint infection and aseptic loosening

Background: To evaluate the meaning of serum CRP, ESR, and D-Dimer in the diagnosis of prosthetic joint infection.

Methods: In a retrospective study, 101 patients presented with osteoarthritis, PJI, and aseptic loosening were divided into three groups according to the type of operation they received in our department from June 2016 to December 2018: group A, 44 patients treated with primary arthroplasty; group B, 31 PJI patients treated with resection arthroplasty and spacer insertion surgery; group C, 26 aseptic loosening patients treated with revision arthroplasty. Data such as gender, age, preoperative serum CRP, ESR, and D-Dimer level were compared among the three different groups.

Results: There are no statistically significant differences when comparing general data such as gender and age in patients from the three different groups. However, Serum CRP level in group B (43.49 ± 10.00 mg/L) is significantly higher than in group A (2.97 ± 0.75 mg/L) and C (4.80 ± 1.26 mg/L). Serum ESR level in group B (49.84 ± 5.48 μg/L) is significantly higher than those in group A (15.28 ± 2.63 μg/L) and C (22.50 ± 3.47 μg/L). Serum D-Dimer level in group B (1.58 ± 0.17 μg/L) is significantly higher than that in group A (0.51 ± 0.50 μg/L), but similar with group C (1.22 ± 0.29 μg/L). There are no statistically significant differences when compared with sensitivity and specificity of CRP, ESR, and D-Dimer in the diagnosis of PJI among patients from the three different groups when D-Dimer > 0.85 μg/L was set as the optimal threshold value for the diagnosis of PJI.

Conclusion: D-Dimer is not a parameter to distinguish between aseptic loosening and PJI.