Serum immunoglobulin D levels in patients with Behçet's disease according to different clinical manifestations

OBJECTIVES: Behçet's disease (BD) is an autoinflammatory disorders mainly characterised by recurrent oral aphthosis, genital ulcers, and uveitis. The involvement of immunoglobulin D (IgD) in BD physiopathology is still unclear. The aim of our study was to assess the role of IgD in BD by comparing circulating levels of IgD in a cohort of BD patients and healthy controls (HC), as well as by correlating IgD levels with BD activity and different clinical presentations. METHODS: Serum IgD and SAA levels were analysed by ELISA assay in ninety-nine serum samples collected from 72 BD patients and in 29 HC subjects. RESULTS: Serum concentration of IgD were higher in BD patients compared with HC (p=0.029), in patients with high serum amyloid A (SAA) levels compared with patients with normal SAA levels (p=0.035), and among subjects with active mucocutaneous involvement compared with other patients (p=0.036). No correlations were identified between IgD serum levels and disease activity assessed by the BD current activity form (BDCAF) (p=0.640). No differences were observed in the IgD serum levels between patients with and without specific disease manifestations. Increased SAA levels (Odds Ratio = 3.978, CI: 1.356 -11.676) and active mucocutaneous BD manifestations (Odds Ratio = 4.286, CI: 1.192 - 15.407) were associated with a high risk for increased IgD serum levels. CONCLUSIONS: Serum IgD levels are significantly increased in BD patients, especially among patients with active mucocutaneous manifestations, suggesting a possible role of IgD in BD pathogenesis and in the onset of mucosal and skin lesions.