Infectious Arthritis

View All Arthritis Types Infectious arthritis is a form of joint inflammation caused by a germ. The germ can be a bacterium, a virus or a fungus. Infection of the joints usually occurs after a previous infection elsewhere in the body.

There is usually only one joint involved, though sometimes two or three joints can become infected. Mostly, infectious arthritis affects the large joints (shoulders, hips, knees), but smaller joints (fingers, ankles) can also be involved.View All Arthritis Types
How common is infectious arthritis?
What are the warning signs of infectious arthritis?
What causes infectious arthritis?
Infectious arthritis is usually not a long-term illness. Most of the time it can be cured if it is treated promptly and properly. Without treatment however, the affected joints can become very damaged within 24 hours of the infection starting and the infection can spread to other parts of the body.

Establishing the correct diagnosis is important, so if your doctor thinks you have infectious arthritis, he or she may ask questions about the symptoms, other medical conditions, recent travel, illnesses, and contact with people who may have had infections. He or she may also perform a physical examination, and order x-rays and other tests to find out what germ is causing the infection. This can be done by using a needle to removing a sample of fluid from the joint so it can be examined. If tuberculosis or a fungus is the suspected cause, sometimes a small piece of tissue from the joint may need to be cut away and examined. If a virus is suspected, a blood test may be done because your body develops cells called antibodies to fight off the virus. These antibodies will show up in a blood test.

People with infectious arthritis are often put in the hospital for treatment. Sometimes affected joints must be drained of excess fluid that has built up. This is done by inserting a needle directly into the joint. This procedure is usually painless. Sometimes the same joint may need to be drained several times if fluid build-up recurs. Further treatment varies depending on what type of germ has caused the infection. Your active involvement in developing your treatment plan is essential.

If infection is considered, antibiotics should be withheld until a fluid culture has been taken from the infected joint unless the patient is clinically unstable. If this is not done then it will be impossible to diagnose the organism responsible for the infection.
Arthritis medications are designed to control a disease, slow its progression, and to help manage pain. There is a wide range of options – with new ones coming on the horizon – so understanding all possible treatments is not easy. 

These medications can be very complex, so you are encouraged to ask for in-depth explanations from your health care team – including pharmacists, who are an excellent source of information. 

To explore this area of treatment, The Arthritis Society has developed a comprehensive expert guide that delivers detailed information on medications used to treat arthritis.

Explore the Arthritis Medications A Reference Guide

The optimal treatment is what is best in each individual case – so speak with your doctor and/or pharmacist about what kind of medications are most appropriate for you.

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