What is Infectious Arthritis?

Infectious arthritis, also known as septic arthritis, is a very serious condition that can cause damage to joints that is at times irreparable. Early and aggressive treatment is usually needed to stave off the long-term side effects of this condition. Caused by an infiltration of bacteria, fungi or viruses in the fluid of a joint, this condition can be extremely painful. But treatments are available.

Who is Most at Risk?

Those who already have arthritis are at the greatest risk for developing infectious arthritis. This is because abnormal joints are more likely to retain fluid, which has a greater likelihood of becoming infected. Anyone with a bloodstream infection is also likely to develop this condition. All it takes is the development of an injury at a joint for blood to accumulate in the area, potentially introducing an infection there.

Typical Symptoms

In adults, symptoms of infectious arthritis can develop over the span of a couple hours or even a few days. The joint itself will become warm and inflamed and be very hard to move as it stiffens up. The area will become sore and swollen. Other symptoms include fever and chills. In infants, this condition might show up as a fever and being generally fussy. They might avoid moving the joint due to pain. Kids may complain of pain in the area and avoid moving the joint at all costs.

Areas Usually Affected

Anywhere on your body that you have a joint can be affected by infectious arthritis. However, some joints are more likely targets than others. For instance, shoulders, knees, hips, elbows, wrists and fingers are common areas that develop this condition. Some bacteria take up residence in certain parts of the body. For instance, gonococcal bacteria might affect several joints at once, while Lyme disease might only affect the knees.

Diagnosis

If you suspect you have developed infectious arthritis, your doctor will typically perform a series of tests to diagnose it. This usually involves taking a sample of fluid from the joint and examining it for the presence of bacteria, fungi or viruses. Blood tests are also taken to see if the bacteria is present in the bloodstream. Knowing the type of bacteria is important so the right antibiotics can be prescribed.

Treatment

Immediate treatment is vital in dealing with infectious arthritis. The joint itself can become seriously damaged very quickly, meaning antibiotics should be introduced as soon as possible--even before tests are completed. They are usually administered intravenously to ensure the treatment is targeted specifically at the joint that's affected. Once your test results come back, your treatment course may change depending on what type(s) of bacteria are discovered in the joint. Extra fluid and pus is removed from the joint to keep swelling down and minimize joint damage. In severe cases, a tube is inserted to help the pus drain. If a fungus is the cause of the infection, an antifungal drug is prescribed. If a virus is the cause, painkillers are prescribed because it usually clears up on its own.