Behçet’s disease is a complex inflammatory condition. It characteristically presents with recurrent oral and genital ulcers. It can also cause inflammation in a number of other areas such as the skin, gastrointestinal tract, lungs, blood vessels, musculoskeletal system and central nervous system. The presentation can vary a lot between patients, with some patients mildly affected and others affected dramatically.
There is a link with the HLA B51 gene. This is a prognostic indicator of severe disease.
Differential Diagnosis
Mouth ulcers are very common. There is a long list of differentials to mouth ulcers:
- Simple aphthous ulcers are very common
- Inflammatory bowel disease (particularly Crohn’s disease)
- Coeliac disease
- Vitamin deficiency (B12, folate or iron)
- Herpes simplex ulcers
- Hand, foot and mouth disease (coxsackie A virus)
- Squamous cell carcinoma
Features
Mouth Ulcers
Patients with Behçet’s disease are expected to get at least 3 episodes of oral ulcers per year. They are painful, sharply circumscribed erosions with a red halo. They occur on the oral mucosa and heals over 2-4 weeks.
Genital Ulcers
Genital ulcers are similar in appearance to the oral ulcers. “Kissing ulcers” are where an ulcer develops on two opposing surfaces so that they are facing each other.
Skin
The skin is very easily inflamed in Behçet’s disease. Particular skin findings in Behçet’s disease are:
- Erythema nodosum
- Papules and pustules (similar to acne)
- Vasculitic type rashes
Eyes
Eye manifestations need emergency review by ophthalmology as they can be sight treating.
- Anterior or posterior uveitis
- Retinal vasculitis
- Retinal haemorrhage
Musculoskeletal System
- Morning stiffness
- Arthralgia
- Oligoarthritis often affecting the knee or ankle. This causes swelling without joint destruction.
Gastrointestinal System
Inflammation and ulceration can occur through the gastrointestinal tract. This tends to affect the:
- Ileum
- Caecum
- Ascending colon
Central Nervous System
- Memory impairment
- Headaches and migraines
- Aseptic meningitis
- Meningoencephalitis
Veins
In Behçet’s disease the veins can become inflamed and this can lead to vein thrombosis. Examples of this are:
- Budd Chiari syndrome
- Deep vein thrombosis
- Thrombus in pulmonary veins
- Cerebral venous sinus thrombosis
These thrombosis tend to stay in place and don’t embolism as they are related to inflammation in the vessel wall.
Lungs
Pulmonary artery aneurysms can develop. If they rupture this can be fatal.
Investigations
Behçet’s disease is a clinical diagnosis based on the features of the condition. The only particular investigation to be aware of is the pathergy test.
The pathergy test involves using a sterile needle to create a subcutaneous abrasion on the forearm. This is then reviewed 24 – 48 hours later to look for a weal 5mm or more in size. It tests for non-specific hypersensitive in the skin. It is positive in Behçet’s disease, Sweet’s syndrome and pyoderma gangrenosum.
Management
Management is coordinated by a specialist, usually a rheumatologist. Other specialities may be involved depending on the affected areas, for example dermatology, ophthalmology and neurology.
Management involves a combination of:
- Topical steroids to mouth ulcers (e.g. soluble betamethasone tablets)
- Systemic steroids (i.e. oral prednisolone)
- Colchicine is usually effective as an anti-inflammatory to treat symptoms
- Topical anaesthetics for genital ulcers (e.g. lidocaine ointment)
- Immunosuppressants such as azathioprine
- Biologic therapy such as infliximab
Prognosis
Behçet’s disease is a relapsing remitting condition. Patients generally have a normal life expectancy and the condition may go in to complete remission. There is an increased mortality with haemoptysis, neurological involvement and other major complications.
Last updated April 2019