The Köebner phenomenon (isomorphic response) is defined as the development of typical lesions of a dermatosis that occur in areas of trauma in previously uninvolved skin. Rare reports have suggested that striae are a form of injury to the skin that can result in koebnerization of psoriasis, vitiligo, and lichen planus. We herein report a 27-year-old female patient with plaque psoriasis who developed psoriatic lesions along striae distensae.

Psoriasis is a chronic, immune-mediated inflammatory and refractory disease. The koebner phenomenon, which can be induced by trauma, is common in psoriasis patients. Herein, we report a patient with psoriasis who was treated by cupping therapy and subsequently developed the koebner phenomenon (KP) at the cupped sites. To our knowledge, it is the first report about cupping therapy leading to KP in a psoriasis patient.

Lichen sclerosus is a chronic inflammatory disease, usually of the anogenital area, that causes intractable itching and soreness. Less commonly, it may have extragenital involvement in 15 to 20% of cases. Lichen sclerosus has been reported at sites of injury as a Koebner phenomenon. We report a case of lichen sclerosus at the site of a tattoo with simultaneous genital involvement.

A 65-year-old man with acute myeloid leukemia 6 was treated by bone marrow allograft, developed a systemic classic chronic graft versus host disease with hepatic, rheumatologic, ophthalmic, and muco-cutaneous involvement. He received systemic corticosteroid, ruxolitinib and extracorporeal photopheresis which resulted in complete remission. During follow-up the patient presented with viral cutaneous warts on his neck and submandibular area. After various subsequent topical treatments, he developed localized cutaneous GVHD without any general GVHD reactivation symptoms. To the best of our knowledge, there has been no description in the literature of a graft versus host disease developing after local immunomodulatory or cytotoxic treatments. Topical therapies are commonly used by dermatologists for superficial skin cancers and some viral skin lesions, in high risk populations such as organ transplant patients with regular follow-up.Practitioners should be made aware of a possible localized cutaneous GVHD reactivation induced by Koebner phenomenon after local therapy.