Prosthetic Joint Infection (PJI) is one of the severe complications following arthroplasty. With the global aging population, the number of patients undergoing primary joint replacement surgeries is increasing, leading to a rise in PJI cases. Although the incidence of PJI is generally low, the impact on patients can be catastrophic. Once an infection occurs, it is further complicated by the rising global antibiotic resistance, imposing a significant economic burden on patients. Therefore, improving the diagnostic rate of PJI is crucial. Currently, various infection markers are used in the diagnosis of PJI. However, there is still a lack of highly sensitive and specific markers to effectively diagnose PJI, necessitating the exploration of new infection markers. This study aims to investigate novel infection markers for the diagnosis of PJI, providing evidence for its diagnosis and subsequent treatment. In this research, we will prospectively collect data from patients undergoing primary joint replacement and those developing PJI from June 2024 to December 2026. These patients will be categorized into non-infection and infection groups. By collecting and analyzing general patient data, surgery-related information, and infection-related indicators from preoperative joint fluid and blood samples, we aim to further evaluate the predictive value of these infection markers for PJI.

Inclusion Criteria:

1. Age ≥18 years old, gender is not limited;
2. The experimental group met the diagnostic criteria of chronic periprosthesis infection after joint replacement according to the 2018 Musculoskeletal Infection Association; The control group was eligible for primary replacement patients who excluded periprosthesis infection.
3. Voluntary and signed informed consent.

Exclusion Criteria:

1. Patients with immune-related arthritis such as rheumatoid and rheumatism were excluded;
2. Radiotherapy and chemotherapy are required due to neoplastic diseases;
3. Receiving systemic glucocorticoid therapy (prednisone > 10mg/ day or equivalent hormone medication);
4. Severe immunodeficiency diseases (such as stage 3 HIV, sickle cell anemia, splenectomy, etc.);
5. Have a history of drug abuse;
6. Use immunosuppressive drugs to treat bone marrow or other transplants;
7. Pregnant, parturient and lactating women;
8. Participating in other clinical trials;
9. Researchers consider other reasons not appropriate for clinical trial participants.

Patients diagnosed with periprosthesis infection or non-periprosthesis infection

Individual participant data (IPD) will be acquired from corresponding author by reasonable reason.

After our paper published.