Pemphigus vulgaris occurring simultaneously on a recent and an old surgical scar due to a Koebner's phenomenon.

Pemphigus vulgaris is an autoimmune bullous disorder involving the skin and sometimes the mucosa. Koebner's phenomenon is encountered when the typical features of a dermatosis are observed on a part of the skin previously subject to friction or trauma. A few cases of pemphigus vulgaris developing after damage to the skin and especially scars have been described. To the best of our knowledge, we report the first case where typical lesions of pemphigus vulgaris appeared simultaneously on a recent and an old scar as the sign of the reactivation of the disease.