skin disorders
Psoriasis
Introduction
Psoriasis is a chronic, recurring disease that causes one or more raised, red patches that have silvery scales and a distinct border between the patch and normal skin. A problem with the immune system may play a role, and some people are genetically predisposed to psoriasis. Characteristic scales or red patches can appear anywhere on the body in large or small patches, particularly the elbows, knees, and scalp. This disease is treated with a combination of medications applied to the skin, exposure to ultraviolet light (phototherapy), and medications taken by mouth or given by injection. Psoriasis is common and varies widely among different populations worldwide. It is likely that psoriasis is underreported among people with dark skin compared with people with light skin. Psoriasis begins most often in people aged 16 to 22 years and aged 57 to 60 years. However, all people of all ages are susceptible. The patches of psoriasis occur because of an abnormally high rate of growth of skin cells. The reason for the rapid cell growth is unknown, but a problem with the immune system is thought to play a role. The disorder often runs in families, and certain genes are associated with psoriasis. Some well-identified triggers of psoriasis include Minor skin injuries Sunburn HIV infection Streptococcal infection, such as strep throat (leading to guttate psoriasis) Medications (especially beta-blockers,chloroquine,lithium, angiotensin-converting enzyme inhibitors,indomethacin,terbinafine, interferon-alfa, immune checkpoint inhibitors, and tumor necrosis factor inhibitors) Emotional stress Alcohol consumption Tobacco smoking Obesity 