Clinical and microbiological evaluation of prosthetic joint infections

Purpose: With this study, it was aimed to evaluate the effectiveness of the sonication method in the microbiological diagnosis of prosthetic joint infections, determine the risk factors affecting morbidity and mortality, and ensure the patients treated by using current guideline recommendations are returned to their daily lives with a new non-infected joint prosthesis. Materials and Methods: The study included 25 patients who were admitted to Manisa Celal Bayar University Hospital, Department of Orthopedics and Traumatology between March 2018 and March 2020 with the diagnosis of prosthetic joint infection and underwent prosthesis removal surgery. The demographic, clinical and laboratory findings of the patients were recorded prospectively. Prosthetic materials, periprosthetic tissue samples and synovial fluid samples were evaluated for microbiological diagnosis. Sonication fluid cultures derived from joint prosthetic components inoculated in both solid and liquid media. Clinical and laboratory findings and treatment observations of the patients were recorded in follow-up sheets. Results: 18 (72%) of the patients were female and 7 (28%) were male. The mean patient age was 69.40 ± 7.04 years. Hypertension (64%) and diabetes mellitus (%36) were the most common comorbid diseases. Although the prosthetic knee joint (63%) of female patients is more often infected; In male patients, the prosthetic hip joint (83%) was commonly infected. Patients admitted to the hospital with delayed onset (44%) and late onset (48%). Recent antibiotic use was present in 11 patients (44%) at the time of the surgery. The most common symptom was joint pain (92%). A statistically significant difference was found between the liquid media cultures of the sonication fluid and the other sample cultures in terms of microorganism XI isolation rates. Culture sensitivites of periprosthetic tissue, synovial fluid, sonication fluid solid media and liquid media were respectively; 40%, 50%, 48%, 96%. S.epidermidis (32%) and S.aureus (24%) were the most common pathogens isolated from samples. Teicoplanin, rifampicin and ciprofloxacin (32%) was the most preferred antibiotic combination. Antibiotic changes were made in 5 patients due to lack of response to the treatment. Three patients had mortality due to postoperative complications and sepsis. Conclusion: Prosthetic joint infections have diagnostic difficulties, require long-term treatment and multidisciplinary approach. In our study, high isolation rates were achieved by inoculating sonication fluid into the liquid media; although low isolation rates were detected with periprosthetic tissue culture. In the light of this information, it was concluded that the use of the sonication method will contribute to the patients to receive appropriate and effective antimicrobial therapy. Keywords: Prosthetic joint infection, sonication, two-stage revision surgery