Psoriasis vulgaris is the most common of the many forms of psoriasis and is characterized by sharply marginated salmon-pink papules and plaques, with silvery-white scale. Psoriasis favors the elbows, knees, scalp, intertriginous areas, and nails. There are many T cells present in psoriatic lesions and a Th1 response is believed to be predominant, with increased levels of cytokines such as IL-1, TNF-alpha, IL-6, and IL-8. Initial eruptions of psoriasis may exhibit a guttate (tear-drop-like) distribution pattern and are often triggered by streptococcal infections. Though not contagious, psoriasis often has psychosocial effects for those affected by it.
Plaque of psoriasis
Psoriasis on extensors