What is Lyme Arthritis?

Lyme disease has gotten a lot of press for its rising numbers over the past couple of decades. The disease, which is spread by ticks, is prevalent in woodsy, deer-heavy locations such as the Northeast. It commonly causes fever, fatigue, and a telltale bullseye rash at the site of the tick bite. Once diagnosed, it's usually easily treated and causes no major complications. But what many people don't realize is that if left undiagnosed and untreated, it can lead to serious problems such as arthritis.

In fact, estimates are that about half of all people who contract Lyme disease end up suffering from arthritis a few months later. The most commonly affected joint is the knee, although it's not unusual for the arthritis to move around. This so-called migratory arthritis means that the knee may swell, stiffen and hurt for awhile, then get better, then another large joint such as the hip will swell, stiffen and hurt, and so on.

The good news about Lyme arthritis is that, unlike other forms of arthritis such as osteoarthritis (caused by progressive wear and tear on the joints) or rheumatoid arthritis (a chronic autoimmune condition), Lyme arthritis generally goes away with treatment. Once your doctor has determined that you have Lyme disease, you will be treated with a course of antibiotics. If the arthritis is causing you discomfort, you may also be prescribed an NSAID, or nonsteroidal anti-inflammatory drug, to relieve pain and inflammation. Only a small percentage of people with Lyme arthritis will go on to experience chronic arthritis that damages cartilage and bone.

How do you know if you have Lyme arthritis? If you suddenly experience pain, swelling and fluid in a large joint, typically the knee, talk to your doctor. She will probably consider Lyme arthritis if you live in a Lyme-heavy area such as the Northeast, or have recently visited a Lyme-heavy area; can recall finding a tick on your body; have experienced fevers or malaise in the past few weeks or months; have seen a red "bullseye" rash anywhere on your body; and do not have any other known conditions such as rheumatoid arthritis or osteoarthritis which would cause these symptoms. A blood test can confirm the diagnosis.

To prevent Lyme disease in the first place, experts say you should wear long pants when walking in or near woods, and check yourself carefully afterwards for ticks. If you find a tick on your body, don't panic. It takes about 24 hours for a tick to attach itself to you and transmit the disease. Remove the tick carefully with tweezers, making sure to get all parts of it out of your skin. Then watch yourself for signs of the illness. And keep flea and tick collars on outdoor pets-they can easily bring ticks into the house, making you a target.



American Academy of Orthopaedic Surgeons, www.aaos.org

Arthritis Foundation, www.arthritis.org.