International diagnostic criteria for leukoaraiosis: 1. Recurrent oral ulcers: 3 recurrent episodes within 1 year. Aphthous ulcers observed by the physician or complained by the patient. 2. Recurrent vulvar ulcers: Aphthous ulcers or scarring of the vulva as observed by the physician or complained by the patient. 3. Ocular lesions: anterior and/or posterior uveitis, presence of cells in the vitreous on slit lamp examination or retinal vasculitis observed by the ophthalmologist. 4. Skin lesions: erythema nodosum, pseudofolliculitis, or papular pustules observed by a physician or complained of by the patient; or acne-like nodules in non-pubertal patients not taking glucocorticoids. 5. The doctor will see the results after a positive pinprick test. Note: Those with recurrent oral ulcers and 2 or more of the other 4 items can be diagnosed with this disease, but other diseases need to be excluded. Other symptoms that are closely related to the disease and facilitate the diagnosis are: arthralgia or arthritis, subcutaneous embolic phlebitis, deep vein embolism, arterial embolism and/or aneurysm, central neuropathy, peptic ulcer, epistaxis, and family history.