Psoriasis is an immune-mediated disease that affects the skin. It is a lifelong condition. There isn’t any cure, though treatments can help to control the symptoms.
Psoriasis happens when the immune system thinks a normal skin cell is a pathogen, and sends out faulty signals that generate over production of new skin cells. Psoriasis is not contagious. Though, psoriasis has been linked to a higher risk of stroke, and treating high blood lipid levels can lead to improvement. There are five types of psoriasis: plaque, guttate, inverse, pustular, and erythrodermic. The most common form, plaque psoriasis, is usually seen as red and white hues of scaly patches showing up on the top first layer of the skin. Some people though, don’t have any dermatological signs or symptoms. The name psoriasis is from the Greek language, meaning “itching condition” (psora “itch” + -sis “action, condition”).
In plaque psoriasis, skin quickly accumulates at these sites, which generates a silvery-white appearance. Plaques regularly appear on the skin of the elbows and knees, but it can affect any area, including the scalp, palms of hands and soles of feet, and genitals. Compared to eczema, psoriasis is more likely to be found on the outer side of the joint.
The disorder is a chronic recurring condition that changes in severity from minor localized patches to complete body coverage. Fingernails and toenails are regularly affected (psoriatic nail dystrophy) and can be seen as an isolated sign. Psoriasis can also cause inflammation of the joints, which is known as psoriatic arthritis. About 10% to 30% of all people that have psoriasis also have psoriatic arthritis.
The cause of psoriasis is not completely understood, but it’s thought to have a genetic component, and local psoriatic changes can be triggered from an injury on the skin known as the Koebner phenomenon.