Diagnosis

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.