VEGFA and chronic idiopathic urticaria: Methods. The concentrations of VEGF and its receptors in plateletpoor plasma (PPP)/plasma were measured using enzyme-linked immunosorbent assay in chronic urticaria: (1) chronic spontaneous urticaria (CSU) with positive autologous serum skin test (ASST), (2) CSU with negative response to ASST, (3) CSU with concomitant euthyroid Hashimoto's thyroiditis (CSU/Hashimoto), (4) delayed pressure urticaria (DPU), and the healthy subjects.