Sonication Leads to Clinically Relevant Changes in Treatment of Periprosthetic Hip or Knee Joint Infection

Abstract

Abstract. Background: Diagnosis of periprosthetic joint infection (PJI) can be troublesome. Sonication can be a helpful tool in culturing bacteria that are difficult to detect with standard tissue cultures. Aim of this study is to evaluate the clinical importance of our standardized sonication protocol in detecting periprosthetic joint infection.Materials and methods: All patients with revision surgery of a hip or knee prosthesis between 2011 and 2016 were retrospectively reviewed and divided in two groups: clinically suspected of infection or not suspected of infection. For both tissue culture and implant sonication, calculations of sensitivity and specificity were performed. Clinical relevance of sonication was evaluated by calculating in which percentage of patients' sonication influenced clinical treatment.Results: 226 patients with revision of a total hip prosthesis (122 patients) or a total knee prosthesis (104 patients) were included. Sensitivity of perioperatively taken tissue cultures was 94.3% and specificity was 99.3%. For sonication sensitivity was 80.5% and specificity was 97.8%.In the infection group eight patients (9%) with only one positive tissue culture and a positive sonication fluid culture with the same pathogen were found.Interpretation: Although sensitivity and specificity of sonication was lower compared to tissue cultures, periprosthetic joint infection could only be established in 8 patients (9%) suspected of infection because of a positive result of the sonication fluid culture.Sonication leads to clinically relevant changes in treatment and seems therefore to be a helpful diagnostic tool in clinical practice.

Challenges in the Microbiological Diagnosis of Implant-Associated Infections: A Summary of the Current Knowledge

“…As a matter of fact, Dudareva et al (2018) demonstrated that the sensitivity of TC was higher than sonication (69% vs. 57%). These findings were further confirmed by a recent study showing higher sensitivity of TC than sonication (94.3% vs. 80.5%), although a certain diagnosis of PJIs was only possible throughout SFC in a not-negligible rate of cases (9%) (Hoekstra et al, 2020). Even more recently, Rieber et al (2021) showed that the overall sensitivity of TC and SFC was similar (91.3% vs. 90.8%, respectively) and, surprisingly, TC showed significantly better results than SFC in detecting polymicrobial infections (97.0% vs. 67.0%).…”

“…Sonication is also able to lyse bacterial cells, and whether bacteria are dislodged from foreign bodies or lysed depends on several factors such as acoustic frequency, energy, temperature and time of ultrasound exposure, duration of sonication and the shape of bacteria (Osmon et al, 2013). Among different sonication protocols (Tande and Patel, 2014), the most widely used for dislodging bacteria from foreign bodies are based on 1-min (Trampuz et al, 2007;Hoekstra et al, 2020) or 5-min duration of sonication at power of 0.22 ± 0.04 W/cm 2 (McDowell and Patrick, 2005;Sampedro et al, 2010;Oliva et al, 2013Oliva et al, , 2016, with or without the centrifugation as a concentration process. The process of sonication is depicted in Figure 1.…”

“…However, there has been debate about the optimal length of incubation of PJI samples and systematic assessment of culture duration has not been defined yet (Virolainen et al, 2002;Neut et al, 2003;Williams et al, 2004;Nelson et al, 2005;Parvizi et al, 2006;Trampuz and Widmer, 2006;Trampuz et al, 2007;Piper et al, 2009;Holinka et al, 2011;Esteban et al, 2013;Portillo et al, 2013Portillo et al, , 2014Shen et al, 2015;Renz et al, 2018). Several authors have recommended incubation for 10-14 days in order to improve the sensitivity (Butler-Wu et al, 2011;Minassian et al, 2014;Portillo et al, 2015;Hoekstra et al, 2020;Rieber et al, 2021) whereas only one study, to our knowledge, proposed 30 days of incubation to detect anaerobic bacteria (Esteban et al, 2008). A 2week incubation period seems to be optimal since early detected species (mostly Staphylococci) emerge predominantly during the first week, whereas late-detected agents (mostly Cutibacterium species, formerly known as Propionibacterium spp.)…”

Diagnostic accuracy of sonication fluid cultures from prosthetic components in periprosthetic joint infection: an updated diagnostic meta-analysis

“…Trampuz et al [13] reported that the sensitivities of PTCs and SFCs were 60.8% and 78.5%, respectively, and found that SFCs detected 14 cases but not PTCs. One recent study claimed that SFC detected positive results in 8 of 87 patients with PJI, while PTC was negative, and Hoekstra et al emphasized that SFC should be used to rule out infection in patients with suspected early aseptic loosening of the prosthesis and negative preoperative synovial fluid culture [23]. Furthermore, previous studies have found a strong trend toward greater sensitivity of SFC against PTC in chronic/delayed PJI [29,31,35,58].…”

Sonication protocols and their contributions to the microbiological diagnosis of implant-associated infections: a review of the current scenario

“…The sensitivity for SFC was 81%, 95% CI (71-88), and the specificity was 97.8%, 95% CI (94-99), which were considerably lower than the results observed for PTC (2x2 contingency table using SPSS version 22.0). Although the sensitivity and specificity of SFC were lower than those of PTC, it is worth noting that 8 patients (9% of the total) suspected of having a periprosthetic joint infection could be definitively diagnosed based on a positive result from SFC ( Hoekstra et al., 2020 ).…”