Phototherapy in dermatology

The successful use of phototherapy in the treatment of various skin diseases, starting from psoriasis, atopic dermatitis, acne, cutaneous T-cell lymphoma, vitiligo, scleroderma and GVHD is well known. The biological action of UV depends on the dose and the wavelength as well as patients sensitivity for UV. Favourable effects of UV on skin diseases include: inhibition of rapid proliferation of cells, initiation of apoptosis, immunomodulation of inflammation, stimulation of proteolytic enzymes, modulation of endothelial cells and innate antimicrobial action. The most important early side effect is sunburn and late side effect is carcinogenesis due to direct DNA damage or immunosuppression. Phototherapy with lamps producing various wavelengths of UV is available: broad band UVB (280-320 nm), narrow band UVB (311 nm), broad band UVA (320-400 nm) for PUVA treatment, UVA1 (340-400 nm), as well as equipment for total body irradiation or localized treatment. Phototherapy is successful as monotherapy or combined with: dithranol, coal tar derivates, retinoids, vitamin D derivates, steroids and with biologicals.