Behçet's disease, also known as Behçet's syndrome and Adamantiades–Behçet’s disease, is a rare, chronic, autoimmune disorder that causes blood vessel inflammation throughout the body. Behçet's disease is characterized mainly by seemingly unrelated symptoms in different parts of the body. The disease is not contagious, therefore, it does not spread from one person to another.

Most of Behçet’s disease symptoms occur as a result of an immune reaction, where the immune system mistakenly attacks blood vessels and causes inflammation. However, the exact cause that triggers this condition with the immune system is not well understood, but certain genes may make some people more prone to develop the disease. Bacteria, viruses and other environmental factors may also trigger the immune system to attack the blood vessels in predisposed individuals.

Behçet's disease is seen throughout the world, but is most prevalent in the Middle East, Far East and the Mediterranean basin. It commonly appears between age 20 and 30, and equally affects men and women, but the symptoms tend to be more severe in men.

Although the exact pathophysiology and etiology of Behçet's disease are still unknown, current evidence suggests that inflammatory reactions arise from disruption of homeostasis in genetically predisposed people, resulting in the hyperfunction of immune cells called neutrophils. Recent genome-wide association studies have confirmed that the histocompatibility antigen HLA-B51 is more common in Behçet's disease patients, but the exact pathogenic mechanism of this relationship is still unknown.

The symptoms of Behçet's disease vary from one patient to another. The most common symptoms are mouth and genital ulcers, skin lesions, inflammation of the eye, and joint pain and swelling.  Some people have only mild symptoms that may clear up on their own, while others may have more serious manifestations, including inflammation of the brain and spinal cord, blood clots, aneurysms and inflammation of the digestive system.

Diagnosing Behçet's disease can be puzzling because it shares symptoms with other illnesses, its symptoms usually do not appear all at one, and there is no specific test to diagnose it. Doctors usually make a diagnosis of Behçet's disease when a person has mouth ulcers at least three times in a year accompanied with at least two of the following: genital ulcers, eye inflammation or the appearance of small red bumps when the skin is pricked in a pathergy test.

Treatment of Behçet's disease is symptomatic, i.e., it is directed to reduce the signs and symptoms of the disease and to prevent serious complications, such as blindness. Treatments aim at specific symptoms, such as topical or oral corticosteroids medication that are applied directly to skin, mouth or genital ulcers and eyes to reduce inflammation and pain.

Other treatments usually involve systemic medications that affect the entire body like corticosteroids, immunosuppressive drugs and biological therapy.

Complications of Behçet’s disease may develop in untreated individuals; for example, severe cases of inflammation of the eyes can lead to permanent loss of vision. However, this is less likely with early and appropriate treatment. Other serious complications include aneurysm ruptures and blood clots that block critical arteries.

There are no known methods for the prevention of Behçet’s disease because the exact cause is unknown.

Behçet’s disease is a chronic disease where there is a very variable phases of relapses and remissions lasting for years. The majority of signs and symptoms occur within the first five years of the disease; in the early stages of the disease attacks may be frequent and last for several weeks. As time progresses the disease enters a remission for longer periods.

Prognosis of Behçet’s disease varies based on the body systems affected. Treatment has improved significantly in recent years, and most patients live out a full life although they will most likely deal with some relapses through the course of their lives. Mortality due the disease is possible, but is very unlikely.

A review published in the British journal Ocular Immunology and Inflammation reported that Behçet’s disease is an important cause of morbidity worldwide. Behçet's disease is most common along the ancient “Silk Road” route in the Far East and Mediterranean basin. The eye is the most commonly involved organ in Behçet’s disease patients.

Behçet's disease is a rare, chronic autoimmune disorder that can potentially affect multiple systems in the body. The disease results in inflammation of blood vessels, hence it is characterized by unrelated symptoms in different parts of the body, including painful mouth ulcers, genital ulcers, eye problems and skin lesions.

The exact cause of Behçet’s disease is not known. However, it is believed to be an autoimmune disorder where the body’ own defense mechanisms mistakenly attack blood vessels and cause inflammation. The reason for this is not understood, but it is possible that genetic and environmental factors may make some people more likely to develop the condition. It has been proposed that a bacterial or viral infection may trigger the immune system to attack the blood vessels in people who are genetically predisposed.

Factors that may increase the risk of Behçet's disease are not fully understood, but the following are thought to play a role:

• Genes: Behçet's disease is usually associated with specific ethnic groups who may have certain genes that are commonly linked to the condition.
• Environmental factors: The specific factors that trigger the condition are not known, but researchers have found that the place of residence is likely to increase the risk; people living in the Middle East and Far East, including Turkey, Iran, Japan and China, are more likely to develop Behçet’s disease.
• Age: Behçet’s disease mainly occur between the ages of 20 and 30 years, but people of all ages can be affected.
• Gender: Behçet’s disease occurs equally in both men and women, but the symptoms tend to be more severe in men.

Behçet’s disease is characterized by recurrent inflammation of blood vessels. Although the exact pathogenesis and etiology of Behçet's disease is still unknown, current evidence suggests that inflammatory reaction arises from disruption of homeostasis in genetically predisposed people, leading to neutrophilic hyperfunction. Lymphocyte function has also been reported as abnormal, with a clonal expansion of autoreactive T cells.

Recent genome-wide association studies have confirmed that the histocompatibility antigen HLA-B51 is more common in Behçet's disease patients; however, the exact pathogenic mechanism of this relationship is still unknown.

The symptoms of Behçet's disease vary depending on the parts of the body affected. Symptoms usually alternate between periods of relapse and remission. The main symptoms of Behçet's disease include:

Mouth Ulcers

Almost all patients with Behçet's disease develop numerous painful mouth ulcers or sores as the earliest sign of the condition. Mouth ulcers most often occur on the tongue, lips, gums and the insides of the cheeks. Ulcers usually heal in 1-3 weeks without leaving scars.

Genital Ulcers

People with Behçet’s disease may experience recurrent red and open sores on the scrotum or on the cervix, vulva or vagina. Genital ulcers are usually painful and may leave scars. These ulcers are not contagious and cannot be spread through sexual intercourse, but it may make having sex painful.

Skin Lesions

Unusual growths of the skin can be recurrent and may vary. They may include widespread acne-like spots called pseudofolliculitis that occur on the arms, legs and trunk, and they may also occur as red, painful nodules on the lower legs called erythema nodosum. Skin lesions often heal within 2 weeks, and may leave permanently discolored areas of skin.

Uveitis

Uveitis is inflammation of a layer of tissue in the eye known as the uveal tract. Uveitis is another common symptom of Behçet's disease that causes painful red eyes, blurred vision and floaters, i.e., dots that move along the field of vision. Sometimes both eyes may be affected at the same time.

Joint Inflammation

Joint inflammation and swelling causes arthritis-like syndrome that leads to pain, stiffness, warmth and tenderness in the affected joints. The knees are most often affected, but inflammation of the ankles, elbows or wrists is also possible. These symptoms usually last 1-3 weeks and can be controlled successfully.

Deep Vein Thrombosis

The inflammation of the lining of the blood vessels associated with Behçet's disease can sometimes lead to the development of a blood clot. Blood clots that develop in one of the deep veins of the body, usually in the legs, is one of the most common type of clots associated with the disease. These clots, called deep vein thrombosis cause pain, swelling, redness, heavy ache, warmth and tenderness in the affected area.

Aneurysms

Inflammation in the large arteries causes their walls to become weaker, leading to aneurysms, or bulges in the walls of the affected arteries.

Gastrointestinal Symptoms

Behçet's disease can lead to inflammation of the stomach and bowel, which may cause a variety of signs and symptoms including abdominal pain, diarrhea, vomiting, loss of appetite and rarely, bleeding.

Nervous System Inflammation

The most serious symptoms of Behçet's disease arise from the possible inflammation of the central nervous system, causing headaches, double vision, loss of balance, seizures, partial paralysis on one side of the body and behavioral or personality changes.

Cerebral Venous Thrombosis

This type of blood clot is less common in patients with Behçet's disease than deep vein thrombosis. It occurs when a blood clot develops in blood vessels located between the outer and inner layers of the brain. Symptoms of this condition may include a severe headache that appears suddenly and stroke like symptoms like slurred speech, seizures, hearing loss, double vision, muscle weakness or paralysis; however, unlike strokes, both sides of the body can be affected.

Sensitive Skin

Behçet's disease can cause pathergy in which skin becomes sensitive to injury or irritation. This is usually detected through a test called a pathergy test.

Diagnosis of Behçet's disease can be challenging, because there is no definitive test that can confirm it. The diagnosis is further complicated because the symptoms do not usually appear at once, and there are other illnesses that have similar symptoms.

International guidelines have been established for the diagnosis of Behçet’s disease. Behçet’s disease is diagnosed when at least three episodes of mouth ulcers occur over a period of 12 months, in addition to two or more of the following symptoms:

• Genital ulcers
• Eye involvement (uveitis)
• Skin lesions
• Positive pathergy test

Some doctors may request other tests, such laboratory tests or CT scans, to rule out other conditions that may have the same signs and symptoms of Behçet's disease.

There is currently no cure for Behçet's disease, so treatment focuses on relieving symptoms and preventing complications. Treatment may only be needed during flare-ups, but it may be long-term in severe cases. Treatment involves:

Symptomatic Treatments

These treatments are directed onto the specific symptoms that a patient with Behçet's disease may have:

• Ulcers and skin lesions:

Topical corticosteroids are applied directly to ulcers on the skin, mouth or genitals to reduce inflammation and pain. They are usually the first recommended treatment and include gels, creams, and mouthwashes. Colchicine tablets can be used to reduce the inflammation in erythema nodosum.

• Eye inflammation:

Corticosteroid or anti-inflammatory eye drops can be used in mild cases to relieve pain and redness. Eye inflammation caused by Behçet's disease can be also treated by taking corticosteroid tablets and Immunosuppressive drugs like azathioprine.

In severe cases where these treatments have not helped, other Immunosuppressive drugs such as mycophenolate mofetil and cyclosporine or biological therapies may also be recommended. Behçet's disease should be carefully observed by an ophthalmologist to prevent developing of any serious complication.

• Joint pain:

Painkillers, such as non-steroidal anti-inflammatory drugs, may help relieve the pain associated with Behçet's disease. Colchicine, an anti-inflammatory tablet often used for gout, may also be beneficial.

Gastrointestinal symptoms

Corticosteroids, immunosuppressive drugs and biological therapies may help reduce the inflammation of the stomach and bowel caused by Behçet's disease.

Although medication is usually successful in treating inflammation, the bowel may become damaged and bleed in severe cases and surgery may be needed to remove the affected area of the intestine.

• Blood clots:

Anticoagulants, or blood thinners, are usually used to treat and prevent blood clots. These help reduce the risk of forming blood clots that block blood vessels. However, anticoagulants are only prescribed if there is no risk of developing aneurysms, because they can increase the risk of aneurysms rupturing and causing bleeding. A combination of corticosteroids or immunosuppressant tablets are often prescribed to reduce the inflammation that leads to blood clots in the vessels.

Blood clots caused by Behçet's disease usually stick to the side of the blood vessel walls, and do not break off and travel through the bloodstream as normal blood clots do. That is why the use of anticoagulants for Behçet's disease remains controversial.

• Central nervous system inflammation

The treatment of the inflammation of central nervous system depends on the severity of symptoms; symptoms like double vision may get better without any need for treatment.

Systemic Treatments

Systemic treatments are medications that travel throughout the bloodstream, reaching and affecting cells all over the body. Moderate to severe cases of Behçet’s disease require treatments to control damage from the disease between flares-ups. Doctors may prescribe:

• Corticosteroids to control inflammation

Corticosteroids, such as prednisone, can be used to reduce the inflammation associated with Behçet's disease. They are available in the form of tablets, capsules or injections. The long-term use of oral corticosteroids may lead to side effects, such as increased appetite and weight gain.

• Immunosuppressive drugs

Immunosuppressive drugs are medications that suppress the activity of the immune system in order to prevent its attacks on healthy tissue and reduce inflammation. Immunosuppressive drugs are available as tablets, capsules or injections, and are usually used in combination with corticosteroids. These medications may increase the risk of infections.

• Biological therapies

These are the newer medications that work by targeting the antibodies involved in the process of inflammation associated with Behçet's disease. Biological therapy is specifically used in patients who have more severe or resistant symptoms because it can be expensive and can also lead to side effects, including flu-like symptoms like muscle pain and fatigue.

Tumor necrosis factor alpha (TNFa) inhibitors are an example of a group of medications that works by targeting antibodies associated with Behçet's disease.

Complications of Behçet’s disease depend on the signs and symptoms. Vision loss from untreated eye inflammation is possible. Other serious complications include blood clots leading to stroke, and aneurysms that rupture and cause bleeding.

There is no way to prevent Behçet’s disease from developing because the exact cause is unknown.

Behçet’s disease is a chronic disease with very variable phases of relapses and remissions lasting for years. In the early stages of the disease attacks may be frequent and last for several weeks, but as time progresses, the disease enters into remissions that lasts for longer periods.

The prognosis of Behçet’s disease varies depending on the systems involved. Treatment has improved significantly, so most Behçet’s disease patients live out a full life, although not without some relapses. Men tend to have a poorer prognosis

Mortality rates for Behçet’s disease are low, and are usually attributed to central nervous system involvement, vascular disease or as a complication of immunosuppressive therapy.

A review published in the British journal Ocular Immunology and Inflammation reported that Behçet’s disease is an important cause of morbidity worldwide. The review found that Behçet's disease is most common along the ancient ‘Silk Road’ in the Far East and Mediterranean Basin, and that he eyes is the most commonly affected organ in patients.

According to a study conducted in the Free University of Berlin, Behçet’s disease is a universal disorder with a varying prevalence. This is seen in that cases occur in 80-370 people per 100,000 inhabitants in Turkey, 2-30 people per 100,000 inhabitants in the Asian continent and 0.1-7.5 people per 100,000 inhabitants in Europe and the USA.