Approximately 50% of chronic urticaria patients demonstrate autoantibodies against high affinity receptor of IgE (Fc RI) or IgE itself. They tend to have a high itch and wheal score, and systemic symptoms. However, in most studies histamine release assays rather than autologous serum skin test were used for their diagnosis. Our objective was to find significance of the autologous serum skin test outcome in predicting the severity of urticaria.