Development and validation of a simple diagnostic tool predictive of the aseptic character of joint effusion in the primary care setting.

In accordance with guidelines and because of the potential gravity that this situation could represent, any joint effusion must be considered as a septic arthritis until proven otherwise, thus justifying an arthrocentesis and an adequate treatment. Nevertheless, because of epidemiology in primary care, this pragmatic attitude is quite commonly obscured and practices vary according to the experience of the doctor and his personal habits. As a result, the arthrocentesis is not commonly performed and anti-inflammatory treatment, whether based on NSAIDs or corticosteroids, is even sometimes administered to the patient despite the contrary guidelines. Although usually effective, this attitude is however not without risks. In this context, it seems interesting to develop a simple, reproducible and applicable diagnostic tool in a primary care setting for predicting the risk of septic arthritis.

This study is therefore aimed at the development and validation of a predictive score based on simple clinical and paraclinical data (such as the macroscopic appearance of the synovial fluid removed) in a patient with an effusion, whatever either the clinical presentation, whether isolated or integrated in a more complex clinical presentation, whether associated with locoregional inflammatory or general signs or not.

Inclusion Criteria:

• Adult patient (age ≥ 18 years)
• Hospitalized in the conventional hospitalization unit or day hospitalization unit or received in consultation within the Rheumatology or Infectious Diseases units at the Le Mans General Hospital
• presenting at least one joint effusion at clinical examination
• Interesting a native, nonoperated joint, accessible to a puncture based on clinical markers, determined by palpatory anatomy
• Affiliated to social security
• No opposition expressed after written information

Exclusion Criteria:

• General antibiotic therapy in progress or completed less than 15 days before
• Failure to perform the arthrocentesis
• Person subject to a legal protection measure, not allowing his compliance with the study
• Participant already included in another study (exclusivity clause)

All adult patients presenting with at least one clinical joint effusion accessible to arthrocentesis, interesting a native non operated joint, without any general antibiotic therapy in the previous 15 days.