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Disease Profile

Behçet disease

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

1-9 / 100 000

US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Behçet's syndrome; Behçet syndrome; BD;


Blood Diseases; Eye diseases; Kidney and Urinary Diseases;


Behçet disease is a chronic multisystem inflammatory disorder characterized by ulcers affecting the mouth and genitals, various skin lesions, and abnormalities affecting the eyes. In some people, the disease also results in arthritis (swollen, painful, stiff joints), skin problems, and inflammation of the digestive tract, brain, and spinal cord.[1][2][3] Although it can happen at any age, symptoms generally begin when individuals are in their 20s or 30s. The disease is common in Japan, Turkey and Israel, and less common in the United States.[2] The exact cause of Behçet disease is still unknown, but it is thought that it is an autoimmune disease, where the abnormal immune activity is triggered by exposure to an environmental agent (such as an infection) in people with a genetic predisposition to develop the disease. Research show that people with Behçet’s disease, especially those of Middle Eastern and Asian descent, have an increased frequency of certain “human leukocyte antigens” (HLAs), specifically HLA-B51, than the general population, which may increase the risk (predispose) to have the disease.[1][2][3]

Treatment is symptomatic and supportive. Research is being conducted on the use of interferon-alpha and with agents which inhibit tumor necrosis factor (TNF) for the treatment of Behçet disease. Behçet disease is a lifelong disorder that comes and goes. Spontaneous remission over time is common for individuals with Behçet disease but permanent remission of symptoms has not been reported.[1][2]


The signs and symptoms of Behçet disease include recurrent ulcers in the mouth and on the genitals, and eye inflammation (uveitis). It usually begins when people are in their 20s or 30s, although it can happen at any age. It tends to occur more often in men than in women. Behçet disease is a multi-system disease and it may involve all organs of the body. Signs and symptoms may include:[1][2] 

  • Sores inside the mouth or genitals: The earliest symptom of Behçet disease is usually painful canker round or oval sores with reddish borders on the mucous membranes that line the mouth (aphthous stomatitis) or in the skin of the genitalia. They may be shallow or deep and may be single or multiple lesions that typically heal within a few days, up to a week or more, without scarring, but frequently recur.
  • Eye problems: Symptoms may include inflammation of the back of the eye (posterior uveitis); inflammation of the anterior chamber (anterior uveitis or iridocyclitis); inflammation of the iris accompanied by pain, tearing (lacrimation); and accumulation of pus (hypopyon iritis). The retina may become inflamed resulting in blurred vision, abnormal sensitivity to light (photophobia), and/or inflammation of the thin membranous layer of blood vessels behind the retina (chorioretinitis). Repeated recurrences may result in the partial loss of vision (decreased visual acuity) or complete blindness if the disease is uncontrolled. In some cases, eye abnormalities may be the first symptom of Behçet disease or they may not develop until several years after the sores of the mouth.
  • Pus-filled lesions and other problems on the skin: Some affected individuals, especially females, may develop lesions that resemble those of erythema nodosum, a skin disorder characterized by the formation of tender, reddish, inflammatory nodules on the front of the legs. These nodules disappear on their own (spontaneously) sometimes leaving faint scars or discoloration (pigmentation). Some people with Behçet disease may develop small eruptions that resemble acne (acneiform eruptions) and/or inflammation that mistakenly appear to affect the hair follicles on the skin (pseudofolliculitis).
  • Pain in the joints (50% of cases): Affected individuals have pain (arthralgia) and swelling in various joints (knees, wrists, elbows and ankles), before, during, or after the onset of the other symptoms.
  • Recurring ulcers in the digestive tract: Symptoms vary from mild abdominal discomfort to severe inflammation of the large intestine and rectum accompanied by diarrhea or bleeding.
  • Problems of the central nervous system (10%-20% of the cases): These symptoms usually appear months or years after the initial symptoms of Behçet disease. Recurring attacks of inflammation involving the brain (parenchymal Neuro-Behçet) or the membranes that surround the brain or spinal cord (meningitis) can result in neurological damage. Symptoms may include headache, cranial nerve palsies, the inability to coordinate voluntary movement (cerebellar ataxia), impaired muscle movements of the face and throat, stroke, memory loss and/or, rarely, seizures.
  • Inflammation of the blood vessels (vasculitis): Involvement of small vessels is thought to drive many of the problems that the disorder causes. In some instances inflammation of the large veins, particularly those in the legs may occur along with the formation of blood clots (thrombophlebitis). The walls of an involved artery may bulge forming a sac (aneurysm). In very rare cases, blood clots from the veins travel to the lungs (pulmonary emboli) resulting in episodes of chest pain, coughing, difficult or labored breathing (dyspnea), and coughing up blood (hemoptysis).

It is especially important to identify Behçet disease when there is ocular, central nervous system or large blood vessel involvement because these as manifestations are usually the most serious.[1]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Joint inflammation

[ more ]

Intermittent migraine headaches
Migraine headache
Migraine headaches

[ more ]

Muscle ache
Muscle pain

[ more ]

Nausea and vomiting
Oral ulcer
Mouth ulcer
Inflammation of testicles
Extreme sensitivity of the eyes to light
Light hypersensitivity

[ more ]

Recurrent aphthous stomatitis
Recurrent canker sores
Subcutaneous nodule
Firm lump under the skin
Growth of abnormal tissue under the skin

[ more ]

Inflammation of blood vessel
30%-79% of people have these symptoms
Abdominal pain
Pain in stomach
Stomach pain

[ more ]

Abnormal blistering of the skin
Blistering, generalized

[ more ]

Joint pain
Easily confused
Mental disorientation

[ more ]

Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

Gastrointestinal hemorrhage
Gastrointestinal bleeding
Weakness of one side of body
Immunologic hypersensitivity
Venous thrombosis
Blood clot in vein
5%-29% of people have these symptoms
Abnormal myocardium morphology
Abnormal pyramidal sign
Aortic regurgitation
Arterial thrombosis
Blood clot in artery
Avascular necrosis
Death of bone due to decreased blood supply
Clouding of the lens of the eye
Cloudy lens

[ more ]

Cerebral ischemia
Disruption of blood oxygen supply to brain
Cranial nerve paralysis
Developmental regression
Loss of developmental milestones
Mental deterioration in childhood

[ more ]

Brain inflammation
Death of body tissue due to lack of blood flow or infection
Coughing up blood
Increased reflexes
Increased intracranial pressure
Rise in pressure inside skull
Keratoconjunctivitis sicca
Dry eyes
Swollen lymph nodes
Intestinal malabsorption
Memory impairment
Memory loss
Memory problems
Poor memory

[ more ]

Mitral regurgitation
Myocardial infarction
Heart attack
Muscle inflammation
Pancreatic inflammation
Pins and needles feeling

[ more ]

Swelling or irritation of membrane around heart
Pleural effusion


The exact cause of Behçet disease is unknown. Most symptoms of the disease are caused by inflammation of the blood vessels (vasculitis). Inflammation is a characteristic reaction of the body to injury or disease and is marked by four signs: swelling, redness, heat, and pain. Doctors think that an autoimmune reaction may cause the blood vessels to become inflamed, but they do not know what triggers this reaction. Under normal conditions, the immune system protects the body from diseases and infections by killing harmful "foreign" substances, such as germs, that enter the body. In an autoimmune reaction, the immune system mistakenly attacks and harms the body's own tissues. Behçet disease is not contagious; it does not spread from one person to another.[3]

Researchers think that two factors are important for a person to develop Behçet disease:[3][4]

  • First, it is believed that abnormalities of the immune system make some people susceptible to the disease. Scientists think that this susceptibility may be inherited; that is, it may be due to one or more specific genes. People with the disease are more likaly to have certain “human leukocyte antigens” (HLAs) in the blood, especially HLA-B51, than the general population. Other genetic markers and their role in the development of Behçet’s disease are being studied.
  • Second, something in the environment, possibly a bacterium (such as Helicobacter pylori) or virus (such as Herpes simplex virus, and parvovirus B19) or exposition to certain substances (such as heavy metals), might trigger or activate the disease in susceptible people.


Although there is no cure for Behçet disease, people can usually control symptoms with proper medication, rest, exercise, and a healthy lifestyle. The goal of treatment is to reduce discomfort and prevent serious complications such as disability from arthritis or blindness. The type of medicine and the length of treatment depend on the person's symptoms and their severity. It is likely that a combination of treatments will be needed to relieve specific symptoms. Patients should tell each of their doctors about all of the medicines they are taking so that the doctors can coordinate treatment.[3]

Topical medicine is applied directly on the sores to relieve pain and discomfort. For example, doctors prescribe rinses, gels, or ointments. Creams are used to treat skin and genital sores. The medicine usually contains corticosteroids (which reduce inflammation), other anti-inflammatory drugs, or an anesthetic, which relieves pain.[3]

Doctors also prescribe medicines taken by mouth to reduce inflammation throughout the body, suppress the overactive immune system, and relieve symptoms. Doctors may prescribe one or more of the medicines listed below to treat the various symptoms of Behçet disease.[3]

Interferon-alfa, azathioprine, and TNF-α blockers may be tried in rare cases of patients with resistant, prolonged, and disabling attacks.[5]

The European League Against Rheumatism (EULAR) has recommendations for the management of Behçet disease.

For ocular disease, azathioprine is the first medication that should be used. For severe eye disease (such as drop in visual acuity, retinal vasculitis, or macular involvement), either cyclosporine A or infliximab may be used in combination with azathioprine and corticosteroids. Interferon-alfa, alone or in combination with corticosteroids, appears to be a second choice in this eye disease.[6]


Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

    Social Networking Websites

    • RareConnect has an online community for patients and families with this condition so they can connect with others and share their experiences living with a rare disease. The project is a joint collaboration between EURORDIS (European Rare Disease Organisation) and NORD (National Organization for Rare Disorders).

      Organizations Providing General Support

        Learn more

        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

        • The Johns Hopkins Vasculitis Center website provides information about different types of vasculitis. Click on the link to access information about Behcet's disease.
        • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
        • Genetics Home Reference (GHR) contains information on Behçet disease. This website is maintained by the National Library of Medicine.
        • The National Eye Institute (NEI) was established by Congress in 1968 to protect and prolong the vision of the American people. Click on the link to view information on this topic.
        • The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) support research into the causes, treatment, and prevention of arthritis and musculoskeletal and skin diseases, the training of basic and clinical scientists to carry out this research, and the dissemination of information on research progress in these diseases. Click on the link to view information on this topic.
        • The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
        • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

          In-Depth Information

          • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
          • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
          • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
          • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
          • PubMed is a searchable database of medical literature and lists journal articles that discuss Behçet disease. Click on the link to view a sample search on this topic.


            1. Calamia KT. Behcet's Syndrome. National Organization for Rare Disorders (NORD). 2018; https://www.rarediseases.org/rare-disease-information/rare-diseases/byID/100/viewAbstract.
            2. NINDS Behcet's Disease Information Page. National Institute of Neurological Disorders and Stroke (NINDS). 2017; https://www.ninds.nih.gov/Disorders/All-Disorders/Behcets-Disease-Information-Page.
            3. Questions and Answers about Behçet’s Disease. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). 2015; https://www.niams.nih.gov/Health_Info/Behcets_Disease/default.asp.
            4. Smith EL, & Yazici Y. Pathogenesis of Behçet syndrome. UpToDate. January 17, 2018; https://www.uptodate.com/contents/pathogenesis-of-behcet-syndrome.
            5. Alnaimat FAA. Behcet Disease. Medscape Reference. 2016; https://emedicine.medscape.com/article/329099-overview.
            6. Bashour M. Ophthalmologic Manifestations of Behcet Disease Treatment & Management. Medscape Reference. 2016; https://emedicine.medscape.com/article/1229174-treatment.

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