High prevalence of HLA-B51 and ocular involvement in Behçet's disease: a multicenter cross-sectional study.

Behçet's disease (BD) is a rare multisystem vasculitis. Globally, BD exhibits a unique geographic distribution, with the highest prevalence along the historic Silk Road. To study the demographics, clinical characteristics, and outcomes of BD in the United Arab Emirates (UAE). A multicenter retrospective chart review study was conducted at hospitals in the UAE from 2008 to 2024. All adult and pediatric patients who were diagnosed with BD by a rheumatologist and treated within the timeframe were included in the study while those who received any alternative final diagnosis were excluded. The results were analyzed using descriptive and inferential statistics. One hundred and twenty-three patients were treated and monitored for BD. Most were female (n = 70, 57%). Their median age was 32 years (24-41), and approximately two-thirds were Emirati (n = 82, 67%). Twelve patients (10%) had a family history of BD, including 7 (6%) with first-degree BD. The time from the initial symptoms to diagnosis was 11.9 months (2.3-31.0). The most common clinical manifestations were oral ulcers (n = 99, 81%), arthralgia (n = 63, 51%), genital ulcers (n = 62, 50%), and ocular involvement (n = 37, 30%). Most of the patients were HLA-B51 positive (n = 92, 84%). At diagnosis, 36 (29%) met the ISG criteria, 73 (59%) met the ICBD criteria, and 50 (41%) met neither criteria. The male patients exhibited more major organ involvement (ocular, neurological, vascular, and cardiac), greater use of corticosteroids and anti-TNFa medications, and greater disease activity than the female patients. Among the patients with isolated ocular manifestations (n = 9) who met neither classification criteria, most were female (56%), with a median age of 37 years (26.5-3.5). None had a family history of autoimmune conditions, and all were HLA-B51 positive. Most of these patients (n = 8, 89%) received corticosteroids, 5 (56%) received azathioprine, and 2 (22%) received anti-TNFa therapies. These findings provide insights into the clinical profile of BD in the UAE. Notably, we found a high proportion of patients with positive HLA-B51 and ocular manifestation. Further research with larger sample sizes is needed to better understand these associations.