The importance of sonication in the diagnosis of prosthetic joint infections

Objective: The objective of this study is to investigate the efficacy of sonication method used to determine the cause in the diagnosis of prosthetic joint infections (PJI). Material and Method: This study included 30 patients who were operated due to prosthesis infection and as a control group 10 patients whose prostheses were removed due to mechanical reasons and who had no sign of infection. Cultures were prepared from these tissue samples through gram staining and conventional methods. The prostheses removed from the patients were put into the sonication device in sterile water with ringer lactate. After sonication, Gram staining, cultures and polymerase chain reaction (PCR) were made. Results: During the Gram staining done prior to the sonication, microorganisms were found in six patients (20%); after the sonication, microorganisms were seen in nine patients (30%), but this difference was not statistically significant (p>0.05). While agents were found in the cultures of 11 patients (36.7%) that were prepared using the conventional method, agents were found in 20 patients (66.7%) with the sonication method. The rate of detecting the agent in the culture prepared after sonication was statistical significantly higher than in the culture prepared with conventional methods (p=0.004). The sensitivity of PCR was found 63.3%. Conclusion: The sonication method of PJI is basically a procedure performed to increase the detectability of microorganisms. We found in the present study that the sonication method was obviously more precise than conventional methods in the microbiological diagnosis of PJI.