SYNOVIAL FLUID D-LACTATE — BACTERIAL-SPECIFIC MARKER FOR INFECTION OF NATIVE AND PROSTHETIC JOINTS

Abstract

Infection of native and prosthetic joints remains a critical disease, associated with both significant mortality and morbidity. The diagnosis of joints infection is extremely difficult since presentation and preoperative tests are not always obvious and precise, while correct and timely diagnosis of septic etiology is crucial. In this case a rapid and accurate test would be helpful.Purpose of the study — тo evaluate the analytical performance and diagnostic capabilities of measuring the synovial fluid D-lactate for early diagnosis of infection in native and prosthetic joints.Material and methods. Test group of patients (n = 86) contained two subgroups – patients with periprosthetic infection (PPI) (n = 58) and patients with bacterial arthritis (BA) (n = 28). Control group (n = 104) also included two subgroups – patients with aseptic instability of implant components (n = 75) and patients with osteoarthritis (OA) (n = 29).Results. The authors observed that SF D-lactate ≥1,2 mmol/l was the optimal cutoff value for identifying patients with bacterial causes. The higher SF levels of D-lactate were observed in patients with BA compared to aseptic causes, (p0,0001), as well as in patients with PJI in contrast to aseptic loosening of prosthesis (p0,0001). In patients with native joints, SF D-lactate had better sensitivity (92,8%) compared to SF leucocytes (66,6%) and percentage of neutrophils (44,4%). D-lactate had better sensitivity for diagnosis of PJI (96,5%, 89,6% and 60,3% respectively). There were no significant differences in SF D-lactate levels due to different bacterial strains.Conclusion. The study demonstrated high analytical performance and diagnostic capabilities of measuring of synovial fluid D-lactate for diagnosis of BA and PJI. It is a rapid and accurate test for differentiating bacterial joint infection from the aseptic inflammatory joint diseases. This procedure can be carried out within less than one hour and be helpful in outpatient setting.