Low-dose narrow-band UVB phototherapy combined with topical therapy is effective in psoriasis and does not inhibit systemic T-cell activation

Psoriasis is a chronic T-cell-mediated inflammatory skin disease which can be treated with topical medication, phototherapy or systemic medication. A subgroup of psoriatic patients does not respond to monotherapy and needs combination therapy. We used low-dose narrow-band UVB phototherapy, combined with balneotherapy, short-contact anthralin, liquor carbonis detergens and calcipotriol for treatment of psoriatic patients in our day care centre. Our purpose was to study the efficacy, induction of erythema and effect on systemic T-cell activation of this combination therapy. Skin reflectance spectrophotometry was used to measure skin erythema. The Psoriasis Area and Severity Index (PASI) was used to evaluate psoriatic patients. Serum soluble IL-2 receptor (sIL2-R) levels were measured by an ELISA. The possible erythematogenic effect of low-dose narrow-band UVB irradiation was studied (skin reflectance spectrophotometer) in a control group of psoriatic patients (n = 11). No induction of skin erythema was seen. Subsequently, this low-dose irradiation regimen was used in combination with topical medication in 26 psoriatic patients. A 90% decrease in the PASI was seen after a mean number of 35 treatment sessions. Seventeen patients (65%) remained in remission during the following 6 months. Serum sIL-2R levels were elevated in all patients (mean 913 U/ml) and did not change during treatment. Our data indicate that low-dose narrow-band UVB can be used successfully, in combination with topical treatment, in a day care setting to treat psoriatic patients. Since sIL-2R serum levels were not decreased, it can be speculated that this treatment does not induce systemic immunosuppression