What are the tests for septic arthritis?

Labs/joint aspirate: Septic arthritis is a serious problem since bacteria destroy joint cartilage. If concerned you should seek medical attention (primary care or orthopaedic surgeon). Blood work can be suggestive of a diagnosis. A joint aspirate analyzed by the lab is usually diagnostic.

Varies: Exam would typically show a swollen, red, hot joint that is extremely painful. Drawing fluid out is the joint and looking at it in the lab is usually the next step, followed by a washout and an antibiotic. MRI scan can sometimes be of help and will usually show a large fluid collection.