[Acute monarthritis].

Common causes of acute monarthritis are osteoarthritis, an acute attack of gout or other crystal arthropathies in older patients or a reactive arthritis or gonococcal arthritis in younger patients. The differential diagnosis should primarily rule out septic arthritis. An arthrocentesis with a microbiological work up and a fresh specimen should be prepared for the diagnosis of crystal arthropathies and if an infectious origin is suspected or if nothing remarkable was found during the primary examination. Further diagnosis und therapy should be performed by a specialist.