591 Ultraviolet radiation alters the skin microbiome composition

Abstract

Background: Anti-FcεRIa and anti-IgE antibodies have recognized to be related with autoimmune chronic spontaneous urticaria (CSU). The in vivo autologous serum skin test (ASST) is widely used to detect autoreactivity in autoimmune CSU, but its meaning is controversial. Objective: To recomfirm whether the ASST correlate the titer of anti-FcεRIa and anti-IgE antibody, disease severity, and effect of cycrosprine in CSU patients. Methods: We performed ASST in 61 CSU patients. Sera from patients and saline as a negative control were injected intradermally to forarms. The wheal response was measured at 30 min after injections, and was taken to be positive when the diameter of wheal is 2 mm bigger than that with saline. Disease severity was evaluated by Urticaria Activity Score (UAS) 7. Anti-FcεRIa antibody or anti-IgE antibody was detected by ELISA. Results: Twenty five out of 61 CSU patients were positive for ASST. The levels of anti-FcεRIa antibody and improvement of UAS7 with oral cycrosporine were significantly higher in ASST positive patients compared to negative patients (P¼ 0.0294, P¼0.00179), and there was no significant diffrence in levels of anti-IgE antibody in both groups (P¼0.189). Conclusions: These findings suggest that detection of anti-FcεRIa antibody may substitute ASST to predict the efficacy of cycrosporine for CSU patients.