EXTRACORPOREAL PHOTOCHEMOTHERAPY IN THE TREATMENT OF TYPICAL AND ATYPICAL LICHEN PLANUS RUBRUM

Abstract

Background: Lichen planus rubrum (LPR) belongs to the group of papulosquamous dermatoses. Pathophysiology of this most common lichenic dermatosis is related to autoimmune destruction of basal keratinocytes. Treatment of LPR includes systemic corticosteroids, cytotoxic agents, immunosuppressants, aromatic retinoids, PUVA-therapy, as well as biological preparations (rituximab, efalizumab), which all are insufficiently effective and associated with multiple side effects and complications. Aim: To evaluate efficacy of extracorporeal photochemotherapy (EPCT) in generalized typical and atypical LPR. Materials and methods: We performed a prospective active-controlled cohort study. Thirty three patients with different types of LPR treated with EPCT were divided into 2 groups. Group 1 included 19 patients with typical generalized (including subacute and chronic) LPR, group 2, 14 patients with atypical (pigmented, follicular, hypertrophic, erosive ulcerated, vulvovaginal/ gingival syndrome) LPR. At 2 hours before a EPCT session patients were administered 8-methoxypsoralen, then mononuclear cells were isolated with a cell separator Haemonetics MCS+ and treated with UV A radiation (at a wavelength from 320 to 400 nm), then monocyte mass was reinfused to the patient. The treatment course consisted of 4 sessions performed every other day. Results: Positive clinical effect and satisfactory tolerability of EPCT were demonstrated in all 33 patients. In patients with generalized subacute typical LPR, EPCT promoted activation of natural immunosuppressive mechanisms (there was no correlation between CD8+ and HLA-DR+ , as well as between CD8+ and CD11b+: r=0.52 (р>0.05) and r=0.35 (р>0.05), respectively). In patients with generalized chronic LPR the treatment led to restoration of immune tolerance to genuine body antigens (correlation between CD16+ and CD11b+ was preserved and correlation between CD16+ and HLA-DR+ was lower: r=0.77 (p<0.05) and r=0.62 (p>0.05), respectively). Conclusion: The data obtained confirms high clinical efficacy of EPCT and its pathophysiological effects at early and later stages of generalized typical LPR.

Keywords

• typical subacute lichen planus rubrum
• typical chronic lichen planus rubrum
• atypical lichen planus rubrum
• extracorporeal photochemotherapy
• immune abnormalities