35 Years of Autologous Serum Skin Test in Chronic Spontaneous Urticaria: What We Know and What We Do Not Know

The autologous serum skin test (ASST) has been used in patients with chronic spontaneous urticaria (CSU) as a means to detect an autoreactivity state for thirty-five years now. Nonetheless, several aspects of this old diagnostic test are still insufficiently defined. Particularly, the nature of the factor(s) responsible for the appearance of the wheal-and-flare skin reaction is still poorly characterized. This article will review our current knowledge about the clinical significance of the ASST and the factors possibly associated with the occurrence of the skin reaction following the intradermal administration of autologous serum that are known so far.