Although the relationship between psoriasis and vitiligo already described from 1890, the relationship between these two diseases are unclear. It has been suggested that the reduction or absence of melanin can be a factor predisposing to develop psoriatic erythematous. further, his appearance on dark-skinned people are low compared with patients clear skin.
In both cases the mechanisms involved autoimmune, which can lead to the correlation. It has been found that both diseases share HLA haplotypes as CW * 6 and B * 27; neuropeptides common, where levels increase necrosis factor , inducing tumor of melanocytes in a patient with vitiligo. Also they have been found that it increased in patients with psoriasis.
In both diseases, production is high proinflammatory molecules such as interleukin-1, Interleukin-6, Interleukin-8, Nuclear factor-kappaB and vasoactive peptide 2-4.
Another cause that can trigger psoriasis coexistence of vitiligo is isomorphic Koebner phenomenon is characterized by the appearance of healthy skin lesions suffering a traumatic process that would stimulate the growth factor of fibroblasts released by keratinocytes damaged, It is leading to endothelial cell proliferation.
This phenomenon has been present in both vitiligo and psoriasis individually and other skin diseases. It described a similar reaction in some units, as common warts, although in these cases it is attributed infection.
Therapies to control these diseases, both topical and systemic and combined, They are similar in most patients.
Phototherapy is a good alternative, especially UVB. Narrow band. It is a first line therapy the diseases described here, with satisfactory results.