Suberythemogenic narrow-band UVB is markedly more effective than conventional UVB in treatment of psoriasis vulgaris

Abstract

Background: Narrow-band UVB (NB-UVB) is a new phototherapy option for psoriasis. Action spectrum studies previously done with different UVB wavelengths suggest that suberythemogenic doses of NB-UVB could be highly effective in treating psoriasis vulgaris. Even so, no comparative studies with suberythemogenic doses of NB versus conventional UVB have been performed previously. Objective: Our purpose was to compare conventional broad-band UVB (BB-UVB) with NB-UVB at suberythemogenic doses for the treatment of psoriasis vulgaris. Methods: Eleven patients were treated using a split-body approach for 6 weeks on a three-times-a-week basis. Outcomes were evaluated by means of Psoriasis Severity Index scores and quantitative histologic measures. Results: We were able to induce clinical clearing in 81.8% of patients after NB-UVB, but in only 9.1% of patients after BB-UVB ( P < .01). Biopsy specimens obtained at the end of treatment revealed that keratin 16 staining was absent in 75% of patients on the NB side compared with none on the BB side, suggesting a reversal of regenerative epidermal hyperplasia by NB-UVB. Conclusion: NB-UVB is superior to UVB-BB in reversing psoriasis at suberythemogenic doses when given three times per week. This schedule was well tolerated by all patients.(J Am Acad Dermatol 1999;40:893-900.)