Leukoaraiosis is an autoimmune vasculitis syndrome that affects the skin, eyes, oral mucosa, external genitalia, cardiovascular system, skeletal muscular system, and nervous system and causes symptoms. Due to the special geographical distribution of leukoaraiosis, it is found in Japan, China, Iran, and Mediterranean countries, and is also known as the “Silk Road Disease”. In the cardiovascular system, the disease may manifest as pericarditis, coronary stenosis or aneurysm, myocarditis, cardiomyopathy, valvular lesions, endocarditis or intra-cardiac thrombosis, aortic and branch aneurysms, pulmonary aneurysms, and venous thrombosis. Leukoaraiosis can invade the descending aorta and cause pseudoaneurysm. Clinical manifestations In addition to the common symptoms of pseudoaneurysm (see the section on pseudoaneurysm for details), patients should also have or have had the typical clinical manifestations of leukoaraiosis: recurrent oral ulcers Recurrent oral ulcers are necessary for the diagnosis of leukoaraiosis. Oral ulcers are usually the first symptom of leukoaraiosis, with other symptoms appearing successively after a few years. The shape and location of leukoplakia oral ulcers are similar to those of common oral ulcers, but they are larger and more painful, rapidly progressing from flattened ulcers to large trabeculae. Leukoplakia ulcers can appear singly or in batches, and do not leave a scar after fading. The common sites of ulcers are the mucosa of the tongue, lips, gums and cheeks, but also the mucosa of the palate, pharynx and tonsils. Oral ulcers can be divided into small ulcers (less than 10 mm in diameter, shallow, surrounded by an erythematous halo, and no scarring after healing), large ulcers (similar in shape to small ulcers but larger in diameter, more painful, longer lasting, and may leave scarring after healing), and herpes-like ulcers (hundreds of small, painful ulcers that appear repeatedly in batches and can fuse into patches). Oral mucosal ruptures can occur secondary to oral ulcers. Genital ulcers 72-94% of patients have had genital ulcers, which are morphologically similar to oral ulcers, but often leave a scar after healing. In males, ulcers are often found in the scrotum and penile ulcers are uncommon. Patients often have epididymitis, and urethritis is not a typical symptom of leukoaraiosis, which can be differentiated from Reiter’s syndrome. In women, ulcers are commonly found on the labia, vagina and cervix, and can cause difficulty in sexual intercourse. In both sexes, groin, perianal and perineal ulcers can occur. Ocular disease is present in 30-70% of patients with leukoaraiosis. 10%-20% of patients have ocular disease as the first symptom, with a higher incidence of ocular involvement and more severe symptoms in men. Ocular disease is usually bilateral and occurs within 2-3 years of developing leukoplakia. Typical pathologic changes are chronic, recurrent, bilateral anterior and posterior uveitis. The characteristic ocular lesion of leukoaraiosis is anterior uveitis with pus accumulation in the anterior chamber, where the inflammatory exudate forms a distinct cellular layer, but this change is seen in only 1/3 of patients. Posterior uveitis and retinal chorioretinitis may be combined in nearly 25% of patients, resulting in loss of vision. Patients may also present with iridocyclitis, scleritis, keratitis, vitreous hemorrhage, optic neuritis, retinal vein occlusion, and retinal neovascularization. Conjunctivitis is very rare. Skin lesions 80% of patients with leukoaraiosis may present with a variety of skin lesions. The most common lesion is erythema nodosum, especially in women. Erythema nodosum is commonly found on the lower extremities and heals with areas of hyperpigmentation. Superficial thrombophlebitis is also common and can be confused with erythema nodosum. Patients may also develop papulopustular lesions and acneiform nodules, which are similar to juvenile acne but are more widespread, appearing on the arms, face, trunk, and buttocks. Patients with leukoaraiosis can specifically develop cutaneous metaplasia – a hyperreactive state of the skin caused by minor trauma. A formal skin metaplasia test is a 20# needle pricked intradermally under sterile conditions without saline injection, and the appearance of an erythematous sterile papule within 48 hours is considered positive. Histologic examination reveals localized neutrophil and lymphocyte infiltration with varying degrees of perivascular exudation. Skin metaplasia is the only specific manifestation of leukoaraiosis, which is positive in 60% of Middle Eastern patients, but only 15% and 5% of Korean and Caucasian patients. Joint disease 2/3 of patients with leukoaraiosis may present with arthropathy. In a minority of patients, arthropathy is the first symptom. The common presentation is non-erosive, non-distorting, non-edematous knee, ankle or wrist pain. Histological examination may reveal the presence of neutrophils and monocytes in the joint fluid with small vasculitis. Treatment Surgical or interventional treatment options and methods are detailed in the section on pseudoaneurysms. Regular medication should be administered preoperatively and postoperatively to control sedimentation and C-reactive protein within normal limits. Commonly used medications include: adrenal glucocorticoids, colchicine, azathioprine, cyclosporine, interferon, and anti-tumor necrosis factor.