Researchers think that two factors are important for a person to get Behcet's disease.
- First, it is believed that abnormalities of the immune system make some people susceptible to the disease. Scientists think that this susceptibility may be inherited; that is, it may be due to one or more specific genes.
- Second, something in the environment, possibly a bacterium or virus, might trigger or activate the disease in susceptible people.
Behcet's disease affects each person differently. Some people have only mild symptoms, such as canker sores or ulcers in the mouth or on the genitals. Others have more severe signs, such as meningitis (inflammation of the membranes that cover the brain and spinal cord). Meningitis can cause:
- a stiff neck
More severe symptoms usually appear months or years after a person notices the first signs of Behcet's disease. Symptoms can last for a long time or may come and go in a few weeks.
Typically, symptoms appear, disappear, and then reappear. The times when a person is having symptoms are called flares. Different symptoms may occur with each flare; the problems of the disease often do not occur together. To help the doctor diagnose Behcet's disease and monitor its course, patients may want to keep a record of which symptoms occur and when.
Since many conditions mimic Behcet's disease, doctors must observe the lesions (injuries) caused by the disorder in order to make an accurate diagnosis.