Abstract
Students of skin diseases have long noted a variety of disease responses and non-responses to trauma and the presence of structural abnormalities. This article will review the series of these responses including: Koebner phenomenon, Wolf isotopic response, Renbök response, Koebner nonreaction, isotopic nonreaction, and other related skin reactions. Because most of these reported phenomena have similar morphological features the diagnosis is often made on the basis of differences in the clinical presentation. Note that some of the cutaneous reactions of similar phenomena have been described using varied nomenclature, further adding to the confusion. In view of this, we believe that at present there is a robust need to define each cutaneous reaction accordingly and classify the various types of these phenomena under a broad universal term or terms. Respecting the idea of differences might facilitate a better understanding of the pathophysiology of these entities. We then will propose an alternative classification system.