Psoriasis

**Semantic type:** Disease or Syndrome

**Definition:** An autoimmune condition characterized by red, well-delineated plaques with silvery scales that are usually on the extensor surfaces and scalp. They can occasionally present with these manifestations: pustules; erythema and scaling in intertriginous areas, and erythroderma, that are often distributed on extensor surfaces and scalp.

**Synonyms:** - psoriasis