In psoriasis, the epidermal cell cycle is accelerated. Cell division in the basal layer occurs every 1.5 days and the migration of keratinocytes to the stratum corneum occurs within just four days or so. Since the cells move to the surface so rapidly, they do not differentiate and mature properly. The stratum corneum is not fully keratinized, and epidermal cells build up abnormally and become scaly. The epidermis in psoriatic lesions is three to five times thicker than normal.
Psoriasis is a single disease with several forms of expression and a range of severity.
The exact cause of psoriasis is unknown, but it is thought that the primary process lies in the immune system with significant input from environmental factors. This is a focus of research for new treatments. The primary goals of care are control of the lesions, minimization of side effects from treatment, and improvement in quality of life. Current treatment utilizes a variety of topical medications as well as ultraviolet light therapy. This MediFocus Guide contains an extensive listing of citations and abstracts of recent journal articles that have been published about this condition in trustworthy medical journals.