Behcet disease

Description

Beh?et disease is a chronic multisystem inflammatory syndrome that may include anterior uveitis, posterior uveitis and retinal vasculitis. The disease has a characteristic diagnostic triad of iritis, oral and genital ulcers. Often the uveitis is of most concern in patients with the disease, as it is usually bilateral and, with recurrent severe episodes, it is potentially blinding.
However, Behget disease may affect many body systems including the pulmonary, gastrointestinal and central nervous systems, making the condition potentially life threatening. Although the onset of the condition may be at any age, the most common onset is at age 20-30 years. The severity of the inflammatory episodes tends to decrease in the later years, although there is a cumulative effect on morbidity owing to the systemic disease. The etiology of Behi^et disease is not known, but infectious, immunological and genetic factors may all contribute.

Symptoms

If uveitis is present in Behget disease, then ocular symptoms may include blurring of vision, photophobia and ocular pain, usually bilaterally.

Signs

In mild cases of Beh^et disease, the oral or genital ulcers, or other skin lesions, may be the only findings; however, occasionally ocular disease may be the initial finding. When present, the uveitis may be severe and recurrent, with hypopyon, iridocyclitis, posterior synechiae, papilledema, vitritis and cystoid macular edema. An occlusive vasculitis may also occur, with retinal hemorrhages, edema and vascular sheathing.

Prevalence

The prevalence of Beh^et disease varies

between countries. It is uncommon to rare (1 in 1000 to 1 in 10 000) in Turkey, Iraq, Iran, Korea and Japan, but very rare (less than 1 in 100 000) in countries such as the USA, UK and Germany. The variation relates to both genetic and environmental factors.

Significance

Behcet disease is potentially sight and even life threatening, requiring prompt investigation and treatment.

Differential diagnosis

Other systemic causes of uveitis, inctuding sarcoidosis, syphilis and tuberculosis. Other ocular causes of anterior chamber reactions include rhegmatogenous retinal detachment, posterior segment tumor and
intraocular foreign body.

Management

Urgent Uveitis associated with Beh?et disease is vision threatening and requires urgent investigation and treatment. Referral to a specialist in inflammatory disease may be also be required for management of the systemic conditions.

Laboratory tests BehQet disease is positive for erythrocyte sedimentation rate, antinuclear antibodies, C-reactive protein and serum haplotyping, although these results may not be diagnostic.

Additional investigations and office

Behcetine skin test, in which the skin is pricked with a sterile needle; the formation of a pustule within a few minutes is a positive result. Fluorescein angiography will show extensive early vascular leakage.

Topical medication Uveitis may be managed with steroids (e.g. prednisolone acetate 1 per cent every 2-6 h, depending on severity). More severe disease may require a sub-Tenon steroid injection.