On the issue of tolerability and safety of phototherapy in patients with psoriasis

Abstract

BACKGROUND: Phototherapy using different wavelengths of the ultraviolet (UV) spectrum has been successfully used to treat a variety of dermatoses. Along with the positive effects of this intervention, there are both acute and long-term side effects that should be taken into account by the clinicians.
 AIM: to study the tolerability and safety of phototherapy (PUVA and UVB-311 nm) in patients with moderate to severe psoriasis.
 MATERIALS AND METHODS: There were 920 patients with psoriasis under our supervision from 2005 to 2021, of which 756 (82%) patients suffered from psoriasis vulgaris, 36 (4%) ― guttate psoriasis, 73 (8%) ― exudative psoriasis, 55 (6%) ― inverse psoriasis. 249/920 (27%) were diagnosed with psoriatic arthritis. Patients with moderate psoriasis received 311 nm UVB therapy (n=473), with severe psoriasis ― PUVA therapy (n=447).
 RESULTS: Out of 920 patients with psoriasis during the entire follow-up period, 385 (41.8%) noted one or more early side effects, which were short-lived and disappeared after the end of the PUVA course if the recommendations were followed. Among the early side effects that occurred during the procedures from taking a photosensitizer, the most common were transient nausea, vomiting, dizziness, headache, transient increase in hepatic transaminases. Side effects from the action of ultraviolet rays were reduced to the manifestation of itching, photodermatitis in the form of erythema, photodermatitis in the form of blisters, photoallergic reaction in the form of papular rash, dry skin, photoconjunctivitis, herpes simplex and even photoonycholysis. Patients treated with UVB-311 nm phototherapy complained on xerosis of the skin, itching, photodermatitis in the form of erythema, burning of the skin as early side effects. Long-term side effects in patients treated with PUVA therapy included lentigo (persistent mottled pigmentation), growth of melanocytic neoplasms, PUVA keratosis. In 11 (2.3%) patients with psoriasis who received UVB-311 nm therapy, new nevi appeared. In 42 (9.6%) patients treated with PUVA therapy and in 17 (3.8%) patients treated with UVB-311 nm, signs of photoaging were detected as well. In our study, only 1 (0.2%) patient was diagnosed with facial skin basal cell carcinoma, who received 5 courses of PUVA (119 procedures).
 CONCLUSION: Our study showed that side effects, especially long-term ones, were fewer and significantly less pronounced in patients treated with UVB-311 nm therapy. Comparing the benefits and risks of phototherapy sessions, we can conclude in favor of the effectiveness, good tolerability and safety of PUVA and UVB-311 nm therapy for the treatment of patients with moderate to severe psoriasis. A dose-dependent effect of photoaging was established: the more phototherapy courses were received, the more pronounced the signs of photoaging were, especially after PUVA therapy.