Heinrich Koebner

Heinrich Koebner (December 2, 1838 - 1904) was a German dermatologist. Koebner was founder of the dermatology clinic at the University of Breslau.

Koebner was a renowned dermatologist known for his research of psoriasis, epidermolysis bullosa simplex and various fungal disorders. He is best-known for the eponymous Koebner phenomenon, also known as isomorphic phenomenon. The Koebner phenomenon is the development of isomorphic pathologic lesions in the traumatized "uninvolved skin" of persons who have cutaneous diseases such as psoriasis. In other words, if a person has psoriasis, trauma is followed by new lesions in the traumatized but otherwise normal skin, and these new lesions are similar to those of the diseased skin in a clinical and histopathological sense.

In 1872, Koebner explained this phenomenon to the Silesian Society for National Culture, by presenting a case in which years after the appearance of an isolated plaque of psoriasis, several traumatic events in remote areas of the body (tattoos, animal bite, suppuration from lymphadenitis, et al), caused outbreaks of psoriasis in the patient at exactly the same location, in the shape of the injured skin. Along with psoriasis, koebnerization may occur with skin disorders such as vitiligo and lichen planus. The following terms are derived from Koebner's name, and are still used by modern dermatologists.
 * koebnerization: word to describe the isomorphic process taking place
 * reverse koebnerization: is seen when an area of psoriasis clears; an isomorphic nonresponse.
 * pseudo-koebnerization: is used to describe the spread of an infectious agent such as warts and molluscum contagiosum.