Behçet's uveitis: eye inflammation in Behçet's disease

Behçet's disease, or Behçet's syndrome, is described by the NHS as a rare and poorly understood condition that causes inflammation of blood vessels and tissues. The cause is unknown, although most experts believe it is an autoinflammatory condition, in which there are repeated episodes of inflammation caused by a problem with the immune system.

The uvea, or uveal tract, is a group of connected structures inside the eye. The NHS says inflammation of the uveal tract is known as uveitis, and that it often affects the eyes in Behçet's disease, sometimes in both eyes at the same time. Behçet's uveitis is the name used when uveitis is caused by Behçet's disease rather than by another cause.

Like other features of Behçet's, eye inflammation tends to come in episodes. The NHS says most people experience flare-ups or relapses followed by remission, and that symptoms often start in adults in their 20s and 30s, although they can start in childhood.

The NHS lists the symptoms of uveitis in Behçet's disease, and says they can develop very suddenly.

• Painful red eyes.

• Sensitivity to light.

• Floaters, which are dots that move across the field of vision.

• Blurred vision.

• Sudden loss of vision.

The NHS says to call 999 or go to A&E if you have sudden blurred vision or sudden loss of vision. For uveitis generally, the NHS says to ask for an urgent GP appointment or call NHS 111 if you have eye pain, sensitivity to light, changes in vision such as flashing or blurring, or very red eyes in one or both eyes, and to go to A&E or call 999 if you cannot see.

If a GP thinks you have uveitis the NHS says they refer you to an eye specialist, and you will usually be seen within 24 hours so treatment can begin quickly. If you already have a diagnosis of Behçet's disease, it is sensible to tell the team about it as soon as eye symptoms start.

There is no definitive test for Behçet's disease itself, according to the NHS. Current guidelines say a diagnosis can usually be made confidently if you have had at least 3 episodes of mouth ulcers in the past 12 months and have at least 2 of genital ulcers, eye inflammation, skin lesions or pathergy (hypersensitive skin), after other causes have been ruled out. Eye inflammation is therefore one of the features used in diagnosis.

For the eye itself, an ophthalmologist examines the inside of the eye. The NHS says that after treatment starts, you will be seen again to check how it is working, to check for side effects and to look for complications such as vision loss.

The NHS says treatment for eye problems in Behçet's often involves azathioprine and corticosteroid medicines, although corticosteroid eyedrops may also be useful. The main groups of medicines used in Behçet's are corticosteroids, immunosuppressants such as azathioprine, ciclosporin and tacrolimus, and biological therapies, which target the processes involved in inflammation.

Biological therapies are described by the NHS as expensive and usually used only if other medicines have not worked, and local hospitals will usually fund them on the NHS only if symptoms are severe and other medicines have been ineffective. Long-term oral corticosteroids can cause side effects including glaucoma and cataracts, so monitoring is part of treatment. Immunosuppressants need blood-test monitoring, often co-ordinated by a specialist nurse, and any signs of infection should be reported promptly.

Some immunosuppressants can cause birth defects and should not be taken if you are pregnant or planning a pregnancy, according to the NHS, so discuss plans with your team.

The NHS says that once Behçet's disease is confirmed you will usually be referred to several different specialists, which may include an ophthalmologist, a rheumatologist, a dermatologist, an oral medicine specialist and a neurologist. There are 3 NHS Centres of Excellence in London, Birmingham and Liverpool, and you may be referred to one to confirm the diagnosis; staff there may also advise other centres. Behçet's UK is the main patient support group.

Private ophthalmology and rheumatology services also exist. The NHS describes Behçet's as needing joined-up care from several specialists, so it is worth making sure your GP and NHS team are kept informed of any private care.

The NHS says some Behçet's symptoms can settle down over time but may never resolve completely. Episodes can return, so knowing the urgent warning signs and having a plan for rapid eye review is important. You may be offered emotional, employment and welfare support, and information on support groups, as part of your care plan.