Japanese Behcet's Disease Registry Study. Subgroup Classification of Behcet's Disease Based on Clinical Findings and Genome-Wide Subtyping to Generate Evidence and Establish a Nationwide Registry

In this study, patients with Behçet's disease (BD) or suspected cases will be classified into subgroups based on clinical information and HLA. New cases will be prospectively evaluated. We will compare cytokine profiles of serum and spinal fluid, gene expression by RNA analysis, and microbiome of saliva and stool to examine biological differences between each subgroup, especially to prove that intestinal type BD is an independent pathology. We will collect BDCAF and blood samples from specific patients at each visit to analyze RNA-seq and cytokine profiles to elucidate the molecular mechanisms. We will also accumulate basic data necessary for the establishment of a nationwide patient registry.