Most of the time scaly red and silver patches of skin caused by psoriasis flare up and then disappear. But in some cases sites where psoriasis occurs, the skin can be left at first white and then turn permanently darker after the psoriasis has gone, leaving skin looking dappled.
However a new study however, has uncovered the molecular roots of skin discoloration associated with psoriasis which could lead to a new treatment for pigmentation changes seen not only in psoriasis, but also in other conditions such as eczema and acne.[quote]Melanocytes, which are what give skin its colour, are present in healthy skin but increase during a psoriasis flare-up. When the flare-up subsides, the cells are pushed toward the surface, causing dark marks to appear.[/quote]
Researchers have discovered that for psoriasis sufferers, two immune system molecules called cytokines play a role in these pigmentation changes. These two molecules are over produced during a psoriasis flare up, leading for the sufferer’s immune system to effectively attack its own skin cells.
Scientists at the Laboratory of Investigative Dermatology at Rockefeller University in New York found that the over productions of the two cytokines were suppressing the pigment production of patients’ melanocytes, which are the cells that produce melanin, the pigment that gives skin its colour.[quote]What they scientists believe happens is that during the psoriasis flare up the production of skin pigment is suppressed, hence why immediate post flare up skin often has white spots in it. Then when the ‘danger’ of the flare up has passed, the two cytokines that were suppressing the pigment production slow down and the body then floods the site with the built up pigment producing melanocytes, making the skin quickly turn from white to dark, resulting in permanent dark spots or dapples.[/quote]
New drugs to suppress the production of the two cytokines could help reducing permanent discolouration after psoriasis flare ups as well as for other skin conditions which can leave permanent skin discolouration such as acne and eczema.