Incidence of ophthalmic involvement in Behcet's disease in the United Kingdom: a British Ophthalmic Surveillance Unit (BOSU) study

Background Behcet's disease (BD) is a relapsing-remitting vasculitis, which can manifest in different organ systems including the eyes. There is currently limited published data describing the incidence of ophthalmic disease within the United Kingdom. The primary aim of this study was to survey the incidence and manifestations of ophthalmic BD prospectively, with a secondary aim of reviewing treatment modalities initiated in first-line therapy. Methods Using the British Ophthalmic Surveillance Unit reporting system between October 2016 and November 2018, we prospectively surveyed the number of cases of BD presenting to UK ophthalmologists. A total of 89 cases of ophthalmic manifestations of BD were reported and complete information was collected on 58 patients. Results 93 eyes of 58 patients were affected. The median age of reported cases was 31 years (range 13-55 years) who were born in 15 different countries. Most cases (n = 35, 60%) had bilateral involvement. Vitritis was the most common ocular manifestation (68%; n = 63) followed by anterior uveitis (46%; n = 43). The greatest causes of visual morbidity were cystoid macular oedema, vitritis and retinal ischaemia. Most patients were prescribed either topical or oral corticosteroids (59%; n = 34), with some given intravitreal or intravenous corticosteroids. Five patients (8.6%) were initiated on disease-modifying anti-rheumatic drugs and one given an anti-TNF monoclonal antibody. Conclusions This is the first prospective study to analyse the incidence of ophthalmic involvement in BD over a 2-year period, finding an annual incidence of 0.04 per 100,000 individuals in the UK.