Is narrowband ultraviolet B monotherapy effective in the treatment of pityriasis lichenoides?

Background Pityriasis lichenoides (PL) is a self-limiting papulosquamous disease that may persist for years and is associated with a high relapse rate. To date, few comparative studies have investigated the efficacy of narrowband ultraviolet B (NB-UVB) phototherapy and other therapies in the treatment of PL. Objectives The present study retrospectively compared the clinical efficacies of NB-UVB phototherapy, systemic therapy, and a combination of NB-UVB and systemic medication in the treatment of PL. Methods Seventy patients diagnosed with PL were enrolled in this study. They were divided into three subgroups: the NB-UVB treatment group; the systemic treatment group; and the combination treatment group. Therapeutic efficacy was evaluated according to whether the subjects demonstrated a complete response (>90% improvement in skin lesions), partial response (50-90% improvement), or no response (<50% improvement) to treatment. Results A 91.9% complete response rate was achieved in the NB-UVB group, whereas only 69.2 and 80.0% of patients achieved a complete response in the systemic and combination treatment groups, respectively; these differences were not statistically significant. The mean treatment periods were 8.3, 5.3, and 7.9weeks in the NB-UVB, systemic, and combination treatment groups, respectively; these differences were also not significant. Conclusions Monotherapy using NB-UVB is effective in achieving a complete response in the treatment of PL and thus eliminates the need for concurrent systemic medication.