Clinical and immunological aspects of extracorporeal photochemotherapy for psoriasis and psoriatic arthritis

Aim. To evaluate the clinical efficiency of extracorporeal photochemotherapy (EPCT) in the treatment of psoriasis (Ps) and Ps associated with psoriatic arthritis (PsA). Subjects and methods. Ninety-three patients with different forms of psoriasis were examined. A study group (SG) comprised 52 patients who were treated with EPCT; a control group (CG) included 41 patients. All the patients received pharmacotherapy generally accepted for these diseases. The SG patients were given additionally EPCT (the patient took 8-methoxypsoralen in a dose of 0.6 mg/kg 1.5-2 hours before the procedure). Mononuclear cells were isolated from the patients' blood in the intermittent-line mode on a Haemonetics MCS+ cell separator. The cell suspension was irradiated with ultraviolet light A (λ=320-400 nm) on a JULIA irradiator at 10-15 ml/min for 30 min and reinfused in the patient. The course of therapy consisted of 4 sessions performed on alternate days. Results. A varying positive effect was obtained in 49 (94%) SG patients; the mean PASI scores fell from 19.7±3.4 to 6.7±2.1 (p<0.05). The DAS reflecting the activity of PsA reduced on average from 3.35±0.7 to 2.16±0.5 (p<0.05), which corresponded to the change of PsA activity from moderate to weak. In CG, the positive effect was less pronounced in 27 (66%) patients, the PASI scores dropped on average from 19.2±3.7 to 12.2±3.1 (p<0.05), DAS in patients with PsA decreased from 3.24±0.8 to 2.95±0.7 (p<0.05). Conclusion. EPCT showed a high efficiency in patients with psoriasis and Ps associated with PsA; the immunological studies demonstrated the pathogenetic direction of the technique.

psoriasis, psoriatic arthritis, extracorporeal photochemotherapy, photopheresis