Tests and diagnosis

By Mayo Clinic Staff

No tests can determine definitively whether or not you have Behcet's disease. Instead, your doctor relies primarily on your signs and symptoms to diagnose Behcet's disease. Your doctor may conduct blood tests or other laboratory tests to rule out other diseases and conditions.

Criteria have been established for the diagnosis of Behcet's disease, but these aren't always essential for the diagnosis of the disease. Your doctor may use other factors for your diagnosis. The classification criteria require:

  • Mouth sores. Because nearly everyone with Behcet's will have mouth sores at some point, this sign is generally necessary for a diagnosis. The diagnostic criteria require mouth sores that have recurred at least three times in 12 months.

In addition, you must have at least two additional signs, such as:

  • Genital sores. Sores that recur may indicate Behcet's disease.
  • Eye problems. An ophthalmologist can identify signs of inflammation in your eyes.
  • Skin sores. A variety of rashes or acne-like sores may be caused by Behcet's disease.
  • Positive pathergy test. In a pathergy test, your doctor inserts a sterile needle into your skin and then examines the area one to two days later. If the pathergy 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.
Mar. 08, 2013