Because this disorder affects many organs, Behçet's syndrome has many symptoms, including:
- Painful ulcers in the mouth. These are usually the first symptom of Behçet's. They resemble canker sores.
- Ulcers on the genitals. When they occur on the penis and scrotum, they can be quite painful. In women, there may be no symptoms.
- Diseases of the eye. Appearing in most patients who have Behçet's syndrome, these cause pain, sensitivity to light and hazy vision. Without treatment, they can cause blindness.
- Skin sores or swelling, redness and tenderness due to minor injuries such as a needle puncture
- Mild arthritis of the knees and other large joints. This develops in about half of all patients with Behçet's.
- Inflamed veins and blood clots. If the inflammation and clot affect the two large veins that return blood to the heart (the inferior and the superior vena cava), there can be life-threatening complications.
- Central nervous system disorders. This range from chronic swelling and inflammation of the brain and the membranes that cover it (meningoencephalitis) to increased pressure inside the skull to life-threatening brain stem and spinal cord lesions.
- Disorders of the stomach and intestines. This can range from discomfort to symptoms that resemble Crohn's disease.
- Swelling and pain in a blood vessel anywhere in the body. This can lead to aneurysms (weak places in the vessel that thin and bulge out) or blood clots. The tiny blood vessels of the kidneys may be affected without symptoms being apparent (asymptomatic focal glomerulonephritis).
Causes and Risk Factors
It is not yet known what causes Behçet's. Cases in Japan and the Mediterranean area suggest that viruses may cause it. There may be genetic factors involved. Another possibility is that the body's defense system (immune system) attacks its own tissues (an autoimmune disorder).
The syndrome generally begins when a person is in his or her thirties. Men are twice as likely as women to develop it. People whose families once lived along the ancient silk route in Mediterranean and some Asian countries, especially Japan, have a greater risk of developing Behçet's syndrome.