Septic arthritis, a bacterial infection of a joint, typically makes a patient very sick. It is most commonly caused by the bacteria Staphylococcus aureus. Treatment may include surgery to clean out the joint as well as intravenous antibiotics for a few weeks.
Identification
Septic arthritis usually presents suddenly in a large joint, such as the knee. Patients develop fever and often appear very sick. The joint may have an effusion, be swollen, or be warm to the touch. Any range of motion of the joint causes severe pain, including any weight-bearing activity such as walking. Septic arthritis is a medical emergency that requires immediate care by a healthcare professional.
Risk Factors
Patients who have an impaired immune system, have persistent bacterial blood infections, use intravenous drugs, and a history of a damaged joint from processes such as rheumatoid arthritis are all at increased risk for developing septic arthritis.
Development
Septic arthritis can develop in three ways. Bacteria in the blood can enter and multiply in a joint, resulting in septic arthritis. There can be direct entrance of bacteria into a joint from trauma or surgery. Finally, bacteria can spread from an adjacent bone into a joint and cause septic arthritis.
Common Pathogens
Staphylococcus aureus is the most common cause of septic arthritis. Other possible pathogens include group A streptococci, Haemophylis influenza and group B streptococci. Less common pathogens include Escherichia coli and Pseudomonas aeruginosa, which are found in intravenous drug users and other immunocompromised individuals.
Treatment
A joint aspiration (removing joint fluid from the knee using a needle) typically is done prior to starting antibiotics. Antibiotics are given intravenously for a few weeks.
A septic joint also requires a surgical washout, in which several liters of fluid are used to irrigate the joint and clear all the enzymes that are damaging the joint. This surgical procedure can be done with an open incision leading into the joint or through tiny incisions, using a camera. In children, Dr Ahmed El-Sayed of the University of Menoufiya in Egypt reported that arthroscopic drainage and washout was an effective method for treating septic arthritis of the hip.
References
- "AAOS Comprehensive Orthopaedic Review"; Dr. Jay Lieberman (editor); 2008.
- "Current Medical Diagnosis and Treatment"; Dr Steven McPhee, Dr Maxine Papadakis; 2007.
- "J Child Ortho": Treatment of early septic arthritis of the hip in children: comparison of results of open arthrotomy versus arthroscopic drainage.
