Effects of azithromycin on intracellular cytokine responses and mucocutaneous manifestations in Behçet's disease.

Objective: The aim of this study was to investigate the effects of azithromycin on mucocutaneous manifestations and ex vivo intracellular cytokine responses in patients with Behçet's disease (BD).

Methods: Ten BD patients with active manifestations and nine healthy controls (HCs) were included in the study. Patients were treated with azithromycin (1500 mg/week) for four weeks. Clinical and immunological responses were evaluated in the pre- and post-azithromycin treatment periods. Peripheral blood mononuclear cells (PBMCs) of patients and controls were stimulated by Streptococcus sanguinis, lipopolysaccharide (LPS), lipoteichoic acid (LTA), and heat shock protein-60 (HSP-60) for three hours. Ex vivo intracellular interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) levels were measured.

Results: Follicular lesions and genital ulcers completely healed, and the number of oral ulcers decreased after treatment (P = 0.000). The stimulated intracellular IFN-γ response to S. sanguinis was higher in BD patients (5.75%) than in HCs (3.9%) before treatment (P = 0.05). Likewise, the pretreatment IFN-γ response was significantly higher than the post-treatment response (1.95%). In BD patients, pretreatment stimulated intracellular IFN-γ responses to LTA (5.8%) were also higher than post-treatment responses (3.15%), but the difference did not reach statistical significance (P = 0.07).

Conclusions: Azithromycin treatment decreased the mucocutaneous manifestations in BD patients and suppressed the intracellular IFN-γ responses of PBMCs to S. sanguinis ex vivo, which suggests this treatment has an immunomodulatory effect.