Diagnosing or excluding a chronic prosthetic joint infection (PJI) prior to revision surgery can be a clinical challenge. To enhance accuracy of diagnosis, several biomarkers were introduced in recent years, but most are either expensive or not available as a rapid test. We compared the diagnostic accuracy of leucocyte esterase (€0.20 per sample), calprotectin (€20 per sample) and alpha defensin (€200 per sample). We prospectively evaluated PJI patients with chronic pain with or without prosthetic loosening between 2017 and 2018. Synovial fluid was collected prior to revision surgery. Leucocyte esterase was measured using a reagent strip (2+ considered as positive), and calprotectin and alpha defensin were measured using a lateral flow immunoassay. Intraoperative cultures (5 periprosthetic tissue samples, synovial fluid and sonication fluid) incubated for 9 days, were used as gold standard. At least two positive cultures of low-grade microorganisms with the same antibiogram were required to diagnose PJI.Aim
Method
Recently, several synovial biomarkers have been introduced into
the algorithm for the diagnosis of a prosthetic joint infection
(PJI). Alpha defensin is a promising biomarker, with a high sensitivity
and specificity, but it is expensive. Calprotectin is a protein
that is present in the cytoplasm of neutrophils, is released upon
neutrophil activation and exhibits anti-microbial activity. Our
aim, in this study, was to determine the diagnostic potential of
synovial calprotectin in the diagnosis of a PJI. In this pilot study, we prospectively collected synovial fluid
from the hip, knee, shoulder and elbow of 19 patients with a proven
PJI and from a control group of 42 patients who underwent revision
surgery without a PJI. PJI was diagnosed according to the current diagnostic criteria
of the Musculoskeletal Infection Society. Synovial fluid was centrifuged
and the supernatant was used to measure the level of calprotectin
after applying a lateral flow immunoassay. Aims
Patients and Methods
