Introduction.
Performing diagnostic aspiration in patients with an established hip joint spacer as part of preoperative diagnosis is a controversial issue. Anyway, the rates of reinfection/recurrence of peri-implant infection during the 2nd stage of RHA remain quite high.
The purpose of the study.
To compare the diagnostic accuracy, specificity and sensitivity of the infection markers used within the framework of preoperative diagnostic protocols in order to exclude reinfection in patients with an established hip joint spacer before the second stage of RHA. To compare and analyze the microbiological landscape obtained at the stages of RHA.
Material and methods.
The evaluation of the diagnostic accuracy of the infection markers used was carried out in order to exclude reinfection/recurrence in 107 patients with an established hip joint spacer. The patients were divided into two groups: group 1 was prospective, an extended diagnostic protocol was used with performing diagnostic aspiration of synovial fluid and blood tests; group 2 was retrospective, a screening diagnostic protocol was used. The reference values of reinfection biomarkers used were based on the "small criteria" of the ICM 2018 protocol.
According to the results of intraoperative microbiological examination of peri-implant tissue samples at the 1st and 2nd stages of RHA, the analysis of the obtained microflora was carried out in order to assess the likely recurrence/reinfection.
Results.
Reinfection among patients of both groups according to the results of intraoperative microbiological examination during the 2nd stage of RHA was diagnosed in 40% of cases: in 1 group of patients – 9 cases, in 2 group of patients – 31 cases. Synovial fluid during preoperative aspiration was obtained in 85% of cases, "dry joint" - in 15%.
Conclusion.
Performing preoperative diagnostic aspiration before the 2nd stage of RHA in patients with an installed spacer allowed in 9% of cases to choose the correct treatment strategy, demonstrating a diagnostic accuracy rate of 82.6%. The prevalent microflora in the structure of hip reinfection during the 2nd stage of RHA is represented by gram-positive coagulase-negative microorganisms.
