Evaluation and interpretation of prosthetic joint infection diagnostic investigations

Authors/contributors
Abstract
Background Total joint arthroplasty (TJA) is considered one of the most successful surgical procedures ever developed. It can successfully provide pain relief, restore joint function, and improve mobility and quality of life. Prosthetic joint infection (PJI) presents with a wide variety and severity of signs and symptoms. It remains a major threat to the outcome of TJA procedures and usually necessitates surgical intervention and prolonged courses of antibiotics. Inappropriate treatment of an unrecognized PJI usually ends with unacceptable and sometimes catastrophic results. The aim The understanding and evaluation of diagnostic investigations are extremely important to properly diagnose PJI, including frequently unrecognized low-grade infections, and to provide healthcare professionals with needed information for the care of patients affected by this condition. This article aims to review most of the methods available in PJI diagnostics, to emphasize the strengths and the weaknesses of each of them, and to provide a guideline on how to select the surgical treatment strategy based on the level of diagnostic certainty during the evaluation period. To safely accomplish this, it is crucial to be aware of the limitations of each diagnostic modality. The focus The emphasis will be on the use and interpretation of the core criteria for PJI diagnosis, including the pathognomonic sinus tract communicating with the implant, purulent synovial fluid, inflammation in the periprosthetic tissue, cell count with differential, microbial growth in the synovial fluid culture, tissue sample cultures, and sonication samples.
Publication
International Orthopaedics
Date
04/2021
Notes

Summary: This article focuses on the evaluation and diagnostic investigations of prosthetic joint infection (PJI) in total joint arthroplasty (TJA) failures. Accurate differentiation between septic and aseptic TJA failure is crucial as it guides appropriate treatment selection. Currently, there is no single test for reliable PJI diagnosis, and multiple diagnostic criteria have been proposed. These criteria vary in sensitivity and specificity, which can result in misdiagnosis or overdiagnosis of PJI. Misdiagnosed PJI patients receive inadequate treatment, while overdiagnosing aseptic failures as PJI can lead to unnecessary overtreatment. Patient evaluation involves gathering information through clinical, histological, cytological, and microbiological parameters. Clinical evaluation includes assessing clinical symptoms, sinus tract communication, and purulence around the implant. Histological evaluation relies on the concentration of neutrophils in periprosthetic membrane or capsular tissue. Cytological evaluation involves joint aspiration for analysis of synovial fluid, including leukocyte count and differential determination.

Microbiological diagnosis is based on synovial fluid culture, tissue sample culture, and sonication. Synovial fluid culture has limitations in sensitivity and may require inoculation in blood culture media for improved results. Tissue sample culture is the most important intraoperative diagnostic procedure, while sonication aids in detaching biofilm microorganisms from implant surfaces for culture.

Various other tests, including serologic markers, alpha defensin, leukocyte esterase, DNA-based molecular diagnostics, synovial markers, and nuclear imaging modalities, show promise in PJI diagnostics but require further validation and study.

Citation
1.
Trebse R, Roskar S. Evaluation and interpretation of prosthetic joint infection diagnostic investigations. International Orthopaedics (SICOT). 2021;45(4):847-855.