The influence of HLA-B51 on clinical manifestations among Japanese patients with Behcet's disease: A nationwide survey

Objectives: To scrutinize the influence of HLA-B51 to each clinical manifestation of patients with Behcet's disease (BD) using a database of the Ministry of Health, Labour and Welfare of Japan. Methods: The database of newly registered patients with BD was obtained from the Japanese Ministry of Health, Labour and Welfare. Patients who met International Criteria for Behcet's Disease (ICBD) and had data for HLA-B51 were selected and analyzed. Results: Among the 3044 analyzable cases, 1334 (43.8%) were men and 1710 (56.2%) were women; the median age was 38 years (IQR 29-48). HLA-B51 was positive for 1334 (44.5%). Prevalence of selected manifestations was 98.5% for oral ulceration, 85.5% for skin lesion, 42.1% for ocular lesion, 69.1% for genital ulceration, and 29.0% for gastrointestinal symptom. HLA-B51-positive patients had higher risk for ocular lesion (OR 1.59, 95%CI: 1.37-1.84; p < .001) and lower risk for genital ulceration (OR 0.72, 95%CI: 0.62-0.84; p < .001) and gastrointestinal symptom (OR 0.65, 95%CI: 0.55-0.77; p < .001). No significant difference was observed for other organ involvement; oral ulceration, skin lesion, positive pathergy test, arthritis, epididymitis, vascular lesion, or neurological manifestation. Subgroup analyses revealed that HLA-B51 was not related to genital ulceration in the cases with an ICBD score of 6 or higher and that HLA-B51 tended to more largely affect the risk of three manifestations for men compared to that for women. Conclusion: HLA-B51 positive is a risk factor for ocular lesion and vice versa for genital ulceration and gastrointestinal symptoms in patients with Japanese BD.