Background and objectives: Primary cutaneous amyloidosis (PCA) is a pruritic disease characterized by amyloid deposition in the skin. Interleukin-31 (IL-31) is a pruritus-mediating cytokine. Fractional carbon dioxide (CO2 ) laser has shown efficacy in the treatment of PCA regarding the clinical appearance, histological pattern, and pruritus. The aim of this study is to assess the effect of fractional CO2 laser on pruritus associated with PCA, and analyze whether this effect is related to IL-31 and IL-31 receptor (R) expression.
Study design/materials and methods: The study included 24 patients with PCA and 24 healthy controls. Each patient received four fractional CO2 laser sessions, 4 weeks apart, using the superficial ablative mode. Skin biopsies were taken from patients before and after treatment, as well as controls, for assessment of IL-31 and IL-31R by real-time polymerase chain reaction.
Results: Treatment resulted in significant improvement of all clinical parameters, including pruritus (P < 0.001). Patients before treatment had significantly higher IL-31 and IL-31R than controls (P = 0.000 for both). In addition, there was a statistically significant decrease in IL-31 and IL-31R after treatment than their values before treatment (P = 0.000 for both).
Conclusion: This study confirms the therapeutic efficacy of fractional CO2 laser in treatment of PCA. Reduction of IL-31 and its receptor seems to be one of the involved mechanisms; however, its relation to improvement of pruritus is still not clear. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
Keywords: IL-31 receptor; fractional carbon dioxide laser; interleukin-31; primary cutaneous amyloidosis.
© 2020 Wiley Periodicals LLC.