Behcet's disease symptoms vary from person to person, can come and go or become less severe over time. Signs and symptoms depend on which parts of your body are affected.

Areas commonly affected by Behcet's disease include:

• Mouth. Painful mouth sores that look similar to canker sores are the most common sign of Behcet's disease. They begin as raised, round lesions in the mouth that quickly turn into painful ulcers. The sores usually heal in one to three weeks, though they do recur.
• Skin. Some people develop acnelike sores on their bodies. Others develop red, raised and tender nodules on their skin, especially on the lower legs.
• Genitals. Red, open sores can occur on the scrotum or the vulva. The sores are usually painful and can leave scars.
• Eyes. Inflammation in the eye (uveitis) causes redness, pain and blurred vision, typically in both eyes. In people with Behcet's disease, the condition can come and go.
• Joints. Joint swelling and pain often affect the knees in people with Behcet's disease. The ankles, elbows or wrists also might be involved. Signs and symptoms can last one to three weeks and go away on their own.
• Blood vessels. Inflammation in veins and arteries can cause redness, pain, and swelling in the arms or legs when a blood clot results. Inflammation in the large arteries can lead to complications, such as aneurysms and narrowing or blockage of the vessel.
• Digestive system. A variety of signs and symptoms can affect the digestive system, including abdominal pain, diarrhea and bleeding.
• Brain. Inflammation in the brain and nervous system can cause headache, fever, disorientation, poor balance or stroke.

When to see a doctor

Make an appointment with your doctor if you notice unusual signs and symptoms that might indicate Behcet's disease. If you've been diagnosed with the condition, see your doctor if you notice new signs and symptoms.

Behcet's disease might be an autoimmune disorder, which means the body's immune system mistakenly attacks some of its own healthy cells. It's likely that genetic and environmental factors play a role.

The signs and symptoms of Behcet's disease are considered to be due to inflammation of the blood vessels (vasculitis). The condition can involve arteries and veins of all sizes, damaging them throughout the body.

Several genes have been found to be associated with the disease. Some researchers believe a virus or bacterium can trigger Behcet's disease in people who have certain genes that make them susceptible to Behcet's.

Factors that might increase your risk of Behcet's include:

• Age. Behcet's disease commonly affects men and women in their 20s and 30s, though children and older adults also can develop the condition.
• Where you live. People from countries in the Middle East and East Asia, including Turkey, Iran, Japan and China, are more likely to develop Behcet's.
• Sex. While Behcet's disease occurs in both men and women, the disease is usually more severe in men.
• Genes. Having certain genes is associated with a higher risk of developing Behcet's.

Complications of Behcet's disease depend on your signs and symptoms. For instance, untreated uveitis can lead to decreased vision or blindness. People with eye signs and symptoms of Behcet's disease need to visit an eye specialist (ophthalmologist) regularly because treatment can help prevent this complication.

No tests can determine whether you have Behcet's disease, so your doctor will rely primarily on your signs and symptoms. Because nearly everyone with the condition develops mouth sores, mouth sores that have recurred at least three times in 12 months are generally necessary for a diagnosis of Behcet's disease.

In addition, a diagnosis of Behcet's disease requires at least two additional signs, such as:

• Recurring genital sores
• Eye inflammation
• Skin sores

Tests you might need include:

• Blood tests or other laboratory tests might rule out other conditions.
• Pathergy test, in which your doctor inserts a sterile needle into your skin and examines the area one to two days later. If the test is positive, a small red bump forms under your skin where the needle was inserted. This indicates your immune system is overreacting to a minor injury.

There's no cure for Behcet's disease. If you have a mild form, your doctor might suggest medications to control the pain and inflammation of flares. You might not need medication between flares.

For more-severe signs and symptoms, your doctor might prescribe medications to control the Behcet's disease throughout your body, in addition to medications for flares.

Treatments for individual signs and symptoms of Behcet's disease

Medications to control signs and symptoms you have during flares might include the following:

• Skin creams, gels and ointments. Topical corticosteroid medicines are applied directly to skin and genital sores to reduce inflammation and pain.
• Mouth rinses. Using special mouthwashes that contain corticosteroids and other agents might reduce the pain of mouth sores.
• Eyedrops. Eyedrops containing corticosteroids or other anti-inflammatory medicines can relieve pain and redness in your eyes if inflammation is mild.

Systemic treatments for Behcet's disease

If topical medications don't help, your doctor might recommend a drug called colchicine (Colcrys, Mitigare) for recurring oral and genital sores. Joint swelling also might improve with colchicine.

Severe cases of Behcet's disease require treatments to control damage from the disease between flares. If you have moderate to severe Behcet's disease, your doctor might prescribe:

• Corticosteroids to control inflammation. Corticosteroids, such as prednisone, are used reduce the inflammation caused by Behcet's disease. Doctors often prescribe them with another medication to suppress the activity of your immune system.

  Side effects of corticosteroids include weight gain, persistent heartburn, high blood pressure and bone thinning (osteoporosis).

• Medications that suppress your immune system. The inflammation associated with Behcet's disease can be reduced by drugs that prevent your immune system from attacking healthy tissues. These drugs may include azathioprine (Azasan, Imuran), cyclosporine (Gengraf, Neoral, Sandimmune) and cyclophosphamide. These drugs can increase your risk of infection. Other possible side effects include liver and kidney problems, low blood counts, and high blood pressure.

• Medications that alter your immune system's response. Interferon alfa-2b (Intron A) regulates the activity of your immune system to control inflammation. It may be used alone or with other drugs to help control skin sores, joint pain and eye inflammation in people with Behcet's disease. Side effects include flu-like signs and symptoms, such as muscle pain and fatigue.

  Medications that block a substance called tumor necrosis factor (TNF) are effective in treating some of the signs and symptoms of Behcet's, especially for people who have more-severe or resistant symptoms. Examples include infliximab (Remicade) and adalimumab (Humira). Side effects might include headache, skin rash and an increased risk of infections.

The unpredictability of Behcet's disease can make it particularly frustrating. Taking good care of yourself might help you cope. In general, try to:

• Rest during flares. When signs and symptoms appear, take time for yourself. Be flexible and adjust your schedule when possible so that you can rest when you need to. Try to minimize stress.
• Be active when you have the energy. Moderate exercise, such as walking or swimming, can make you feel better between Behcet's disease flares. Exercise strengthens your body, helps keep your joints flexible and can improve your mood.
• Connect with others. Because Behcet's is a rare disorder, it may be difficult to find others with the disease. Ask your doctor about support groups in your area. If it's not possible to connect with someone close, the American Behcet's Disease Association offers message boards and chat rooms where you can connect with other people who have Behcet's.

You're likely to start by seeing your primary care doctor. He or she may refer you to a doctor who treats arthritis and other rheumatic illnesses (rheumatologist).

Depending on your signs and symptoms, you might also need to see an ophthalmologist for eye problems, a gynecologist or urologist for genital sores, a dermatologist for skin problems, a gastroenterologist for digestive difficulties, or a neurologist for symptoms that involve the brain or central nervous system.

Here's some information to help you get ready for your appointment.

What you can do

Make a list of:

• Your symptoms, including when they began and how severe they are
• Key personal information, including major stresses and recent life changes
• All medications, vitamins and supplements you take, including doses
• Questions to ask your doctor

Ask a family member or friend to come along to help you remember the information you receive.

For Behcet's, questions to ask your doctor include:

• What do you think is causing my symptoms?
• What tests do I need? Do they require preparation?
• Is my condition temporary or long lasting?
• What are my treatment options, and which do you recommend?
• I have another medical condition. How can I best manage these conditions together?
• Do you have brochures or other printed material that I can take? What websites do you recommend?

What to expect from your doctor

Your doctor is likely to ask you questions, such as:

• Do you have your symptoms all the time, or do they come and go?
• What, if anything, seems to improve your symptoms?
• What, if anything, seems to worsen your symptoms?
• Does anyone in your family have a similar illness?