Koebner phenomenon of discoid lupus erythematosus on old tattoos.

The Koebner phenomenon is the development of lesions in traumatized skin, often with spontaneously occurring lesions elsewhere. We report a case of a woman in her 20 s presenting with discoid lesions superimposed on tattoos that she obtained many years ago. Although a few case reports have been published describing development of lesions on red tattoos attributed to photosensitivity, or koebnerization occurring less than a month following tattoo placement, our patient demonstrates a unique delayed development of discoid lesions years after obtaining her tattoos in non-sun exposed skin. Patients with conditions associated with the Koebner phenomenon must be counseled regarding forms of preventable trauma such as tattoos, and should be made aware that the Koebner phenomenon may not only manifest immediately, but can also present many years later.