Inflammatory arthritis. A healthy immune system is protective. It generates internal inflammation to get rid of infection and prevent disease. But the immune system can go awry, mistakenly attacking the joints with uncontrolled inflammation, potentially causing joint erosion and may damage internal organs, eyes and other parts of the body. Rheumatoid arthritis and psoriatic arthritis are examples of inflammatory arthritis. Researchers believe that a combination of genetics and environmental factors can trigger autoimmunity. Smoking is an example of an environmental risk factor that can trigger rheumatoid arthritis in people with certain genes.

With autoimmune and inflammatory types of arthritis, early diagnosis and aggressive treatment is critical. Slowing disease activity can help minimize or even prevent permanent joint damage. Remission is the goal and may be achieved through the use of one or more medications known as disease-modifying antirheumatic drugs (DMARDs). The goal of treatment is to reduce pain, improve function, and prevent further joint damage. 

Infectious arthritis.  A bacterium, virus or fungus can enter the joint and trigger inflammation. Examples of organisms that can infect joints are salmonella and shigella (food poisoning or contamination), chlamydia and gonorrhea (sexually transmitted diseases) and hepatitis C (a blood-to-blood infection, often through shared needles or transfusions). In many cases, timely treatment with antibiotics may clear the joint infection, but sometimes the arthritis becomes chronic. 

Metabolic arthritis. Uric acid is formed as the body breaks down purines, a substance found in human cells and in many foods. Some people have high levels of uric acid because they naturally produce more than is needed or the body can’t get rid of the uric acid quickly enough. In some people the uric acid builds up and forms needle-like crystals in the joint, resulting in sudden spikes of extreme joint pain, or a gout attack. Gout can come and go in episodes or, if uric acid levels aren’t reduced, it can become chronic, causing ongoing pain and disability.

Diagnosis

Arthritis diagnosis often begins with a primary care physician, who performs a physical exam and may do blood tests and imaging scans to help determine the type of arthritis. An arthritis specialist, or rheumatologist, should be involved if the diagnosis is uncertain or if the arthritis may be inflammatory. Rheumatologists typically manage ongoing treatment for inflammatory arthritis, gout and other complicated cases. Orthopaedic surgeons do joint surgery, including joint replacements. When the arthritis affects other body systems or parts, other specialists, such as ophthalmologists, dermatologists or dentists, may also be included in the health care team.

Living With Arthritis

There are many things that can be done to preserve joint function, mobility and quality of life. Learning about the disease and treatment options, making time for physical activity and maintaining a healthy weight are essential. Arthritis is a commonly misunderstood disease. The Arthritis Foundation is the only nonprofit organization dedicated to serving all people with arthritis. Its website, arthritis.org, has many resources for learning about arthritis, practical tips for daily living and more.