Behcet's Disease
Behcet's disease is a rare, chronic inflammatory disorder. The cause of Behcet's disease is unknown, although there have been reports of a virus found in some individuals with the disease. Behcet's disease generally begins when individuals are in their 20s or 30s, although it can happen at any age. It tends to occur more often in men than in women. Symptoms of Behcet's disease include recurrent ulcers in the mouth (resembling canker sores) and on the genitals, and eye inflammation. The disorder may also cause various types of skin lesions, arthritis, bowel inflammation, meningitis (inflammation of the membranes of the brain and spinal cord), and cranial nerve palsies. Behcet's is a multi-system disease; it may involve all organs and affect the central nervous system, causing memory loss and impaired speech, balance, and movement.
The effects of the disease may include blindness, stroke, swelling of the spinal cord, and intestinal complications. The disease is common in Japan, Turkey and Israel, and less common in the United States.
Symptoms and Signs of Behcet's disease
Behcet's disease is virtually unparalleled among the vasculitides in its ability to involve blood vessels of nearly all sizes and types, ranging from small arteries to large ones, and involving veins as well as arteries. Because of the diversity of blood vessels it affects, manifestations of Behcet’s may occur at many sites throughout the body. However, the disease has a predilection for certain organs and tissues; these are described below.
- Eye
- Mouth
- Skin
- Lungs
- Joints
- Brain
- Genitals
- Gastrointestinal Tract
- Behcet’s may cause either anterior uveitis (inflammation in the front of the eye) or posterior uveitis (inflammation in the back of the eye), and sometimes causes both at the same time.
- Anterior uveitis results in pain, blurry vision, light sensitivity, tearing, or redness of the eye.
- Posterior uveitis may be more dangerous and vision–threatening because it often causes fewer symptoms while damaging a crucial part of the eye — the retina.
- Painful sores in the mouth called “aphthous ulcers”(pictured below). These are very similar in appearance to ulcers that frequently occur in the general population, usually as a result of minor trauma. In Behcet’s, however, the lesions are more numerous, more frequent, and often larger and more painful. Aphthous ulcers can be found on the lips, tongue, and inside of the cheek. Aphthous ulcers may occur singly or in clusters, but occur in virtually all patients with Behcet’s.
Skin
- Pustular skin lesions that resemble acne, but can occur nearly anywhere on the body. This rash is sometimes called “folliculitis”.
- Skin lesions called erythema nodosum: red, tender nodules that usually occur on the legs and ankles but also appear sometimes on the face, neck, or arms. Unlike erythema nodosum associated with other diseases (which heal without scars), the lesions of Behcet’s disease frequently ulcerate.
- Aneurysms (outpouchings of blood vessel walls, caused by inflammation) of arteries in the lung, rupture of which may lead to massive lung hemorrhage.
- Arthritis or “arthralgias” (pain in the joints not accompanied by joint swelling).
- Central nervous system involvement is one of the most dangerous manifestations of Behcet’s. The disease tends to involve the “white matter” portion of the brain and brainstem, and may lead to headaches, confusion, strokes, personality changes, and (rarely) dementia. Behcet’s may also involve the protective layers around the brain (the meninges), leading to meningitis. Because the meningitis of Behcet's disease is not associated with any known infection, it is often referred to as “aseptic” meningitis.
- Male — painful genital lesions that form on the scrotum, similar to oral lesions, but deeper.
- Female — painful genital ulcers that develop on the vulva.
- Ulcerations may occur anywhere in the gastrointestinal tract from the mouth to the anus. The terminal ileum and cecum are common sites. Involvement of the GI tract by Behcet’s may be difficult to distinguish from inflammatory bowel disease (such as Crohn’s disease).
Behcet's disease is one of the few forms of vasculitis in which there is a known genetic predisposition. The presence of the gene HLA–B51 is a risk factor for this disease. However, it must be emphasized that presence of the gene in and of itself is not enough to cause Behcet’s: many people possess the gene, but relatively few develop Behcet’s. Despite the predisposition to Behcet’s conferred by HLA–B51, familial cases are not the rule, constituting only about 5% of cases. Thus, it is believed that other factors (perhaps more than one) play a role. Possibilities include infections and other environmental exposures.
Treatment
For disease that is confined to mucocutaneous regions (mouth, genitals, and skin), topical steroids and non–immunosuppressive medications such as colchicine may be effective. Moderate doses of systemic corticosteroids are also frequently required for disease exacerbations, and some patients require chronic, low doses of prednisone to keep the disease under control.
In the event of serious end–organ involvement such as eye or central nervous system disease, both high doses of prednisone and some other form of immunosuppressive treatment are usually necessary. Immunosuppressive agents used in the treatment of Behcet's disease include azathioprine, cyclosporine, cyclophosphamide, and chlorambucil. With organ- or life-threatening disease, the combination of prednisone and either cyclophosphamide or chlorambucil (both of which are from the same class of drug — “alkylating agents”) is the preferred therapy.
Informations obtained from National Institute of Health.