Prospective Study of Patients Treated for Bone and Joint Infection (BJI) Due to Staphylococcus Aureus, Aiming at Identifying Biomarkers of Diagnosis Interest in Chronic BJI

Overview

There are more than one million (\> 40,000 cases per year in France) of osteoarticular infections (OAI) yearly in the world. The number of these infections is constantly increasing due to an increase in life expectancy associated with an increase in prosthesis fitting, as well as an increase in comorbid factors. These are severe pathologies associated with mortality (5%) and significant morbidity (40%), responsible for functional sequelae with an individual cost (prolonged hospitalization, altered quality of life, disability) and societal (sick leave, partial disability). or total, temporary or permanent) extremely high. In addition, reinfection rates within two years of treatment are high. The BJIs are a group of clinical entities that have in common the invasion and progressive destruction of bone and cartilage tissue by bacterial-like microorganisms. Staphylococcus spp is the main pathogen (\>50%) in BJI and is associated with particularly difficult to treat infections, with a high rate of chronicity and relapses, especially in case of implanted material. The difficulty in managing these infections is partly linked, on the one hand, to the fact that the pathogens are in "persistent" metabolic forms and in intracellular reservoirs which make them insensitive to conventional antibiotics and, on the other hand, the absence of reliable markers of the infection and above all of its clinical resolution, which complicates clinical trials. ESPRI-IOAC is a consortium of 4 partners (private-public) from Lyon area and which aims at: * studying the translational value of BJI preclinical models * identifying biomarkers of infection in preclinical models and at assessing them in a prospective study. The current study is part of the global ESPRI-IOAC consortium, and represent the clinical application. It is a prospective study of patients treated for BJI in the infectious disease department of the Hospices Civils de Lyon, La Croix-Rousse, for osteo-articular infections due to Staphylococcus aureus, or for simple mechanical revision or for cruciate ligament surgery, the objective of which is to highlight biomarkers of interest in the diagnosis of chronic BJI and, or predictive of the therapeutic response. The translational value of the experimental models used in the BJI will also be studied.