[Modern aspects in the pathogenesis of urticaria with special reference to intolerance phenomena].

The chronic urticaria remains till now a "vexing problem" (Sheldon, 1954), because its etiopathology can be clarified only in about 20-30%. Five different immunologic mechanisms, two nonimmunologic mechanisms and two important manifestation factors are found. The physical triggering (12-17%) and the so-called aspirine/additiva provocation (26%) seem to be the most frequent causes of urticaria. Exogenic antigens are identified only in 3-8% of cases. The unspecific reaction phase of urticaria can be different too, although the degranulation of mast cells with histamine-deliberation is found very often. In hereditary urticaria and in pressure urticaria histamine-deliberation seems not to be important.