Who’s at Risk for Septic Arthritis?
Young children and elderly adults are most likely to develop septic arthritis. People with open wounds are also at a higher risk for septic arthritis. In addition, people with a weakened immune system and those with pre-existing conditions such as cancer, diabetes, intravenous drug abuse, and immune deficiency disorders have a higher risk of septic arthritis. In addition, previously damaged joints have an increased likelihood of becoming infected.
What Are the Symptoms of Septic Arthritis?
Symptoms of septic arthritis usually come on rapidly with intense pain, joint swelling, and fever. Septic arthritis symptoms may include:
- Fatigue and generalized weakness
- Inability to move the limb with the infected joint
- Severe pain in the affected joint, especially with movement
- Swelling (increased fluid within the joint)
- Warmth (the joint is red and warm to touch because of increased blood flow)
How Is Septic Arthritis Diagnosed?
A procedure called arthrocentesis is commonly used to make an accurate diagnosis of septic arthritis. This procedure involves a surgical puncture of the joint to draw a sample of the joint fluid, known as synovial fluid. Normally, this fluid is sterile and acts as a lubricant.
During arthrocentesis, a needle is inserted into the affected joint to collect fluid from the joint. The fluid sample is sent to a lab for evaluation. The lab will perform a white cell count on the fluid, which will usually very high. The lab will also try to culture bacteria or other organisms. This will help the doctor determine if an infection is present and which organism is causing it.
X-rays are typically done to look for joint damage. Blood tests can also be used to monitor inflammation. MRI scanning is sensitive in evaluating joint destruction but is less useful in the early stages . Blood tests can also be taken to detect and monitor inflammation.