Septic Arthritis in Children

Septic arthritis is an infection found in the fluid and tissue of one or more joints. The infection presents itself with fever, chills, inflammation, swelling and loss of function in those joints. Septic arthritis can affect infants and children, mainly in the hips, knees and shoulders. It is important to receive timely treatment for this condition to prevent permanent joint damage.

Causes

• Septic arthritis occurs when an infectious agent, usually bacteria, is introduced into the joint fluid or tissue. This can be blood borne, occur during surgery or result from a direct injury. Staphylococci, Haemophilus influenzae, gram-negative bacilli and the bacteria responsible for Lyme disease are the most common culprits in children.

Risk Factors

• According to the Milton S. Hershey Medical Center College of Medicine at Penn State University, those most at risk for septic arthritis are patients with a pre-existing condition such as rheumatoid arthritis, cancer, diabetes, sickle cell anemia or lupus. Undergoing arthroscopic surgery or prosthetic joint surgery can also increase the risk of infection.

Symptoms

• Symptoms of septic arthritis include a sudden onset of joint pain, localized swelling, redness, warmth, chills and a fever. Children have also reported nausea or vomiting. These symptoms can mimic other conditions so consult a doctor for an official diagnosis.

Diagnosis

• Septic arthritis must be diagnosed quickly before permanent damage is done to the affected joint. The doctor will collect information such as symptoms and medical history. Blood tests and a blood culture will be performed to check for the presence of infection. Arthrocentesis, in which synovial fluid is removed from the affected joint with a needle and tested for infection, may be performed.An x-ray may be ordered if there is already suspected damage to the joint. Based on the cumulative findings and ruling out other causes, a definitive diagnosis can be made.

Treatment

• Treatment of septic arthritis will depend on a few factors, such as the child's medical history, extent of the condition and course of the disease. Antibiotics are usually administered immediately for bacterial infections. Viral infections are allowed to run their course. Excess fluid may be drained if present. Pain management is also used in the form of medications, immobilization of the joint and physical therapy. The prognosis is excellent for those receiving prompt treatment, although some patients may develop osteoarthritis or deformed joints. Reconstructive surgery may be needed in severe cases.