[Septic arthritis in adults]

Septic arthritis is a true rheumatological emergency requiring immediate and thoughtful effort for rapid diagnosis establishment and treatment initiation. Children and elderly persons as well as immunocompromised individuals, patients with pre-existing joint damage and with inflammatory rheumatic joint diseases are preferentially affected. Bacteremia, joint surgery and intra-articular injections pose risk situations for the development of joint infections. The most frequent causative organism is Staphylococcus aureus but other relevant pathogens include coagulase-negative staphylococci, streptococci and mycobacteria. Synovial fluid analysis (e.g. appearance, cell count and microbiological examination) is the most important step to establish the diagnosis. The two main components of therapy consist of joint drainage and antibiotic treatment. The approach to periprosthetic joint infections depends on the duration of symptoms, causative organism and individual factors.