Renbök-Phenomenon

Rudolf Happle, 1991

Renbök is a palindrome of the word Köbner (see below Köbner phenomenon). With the Renbök phenomenon Rudolf Happle described the so-called inverse Köbner effect. Patients with psoriasis and alopecia areata universalis showed a normal hair growth in the area of the psoriasis lesions.

Note: The pathogenetic specificity of the immunological process underlying this phenomenon is unknown. In any case, a pre-existing dermatosis (psoriasis) causes the protection against the appearance of another skin disease (alopecia areata). In other words: in the immunosituational rooming of the psoriatic lesion, a systemic autoimmunological reaction as in alopecia areata totalis cannot have an impact.

The extent to which this phenomenon is an inverse "Köbner phenomenon" remains to be seen.

A similar immune mechanism was induced by the artificial, now obsolete treatment of alopecia arata via contact sensitization with diphenylcyclopropenone (DPCP) (Harris JE et al. 2010). Again, 2 different immunological mechanisms neutralize each other.