Plaque-type psoriasis is the most common form of the disease and is commonly referred to as psoriasis vulgaris (Camisa 56). Plaque-type psoriasis is characterized by inflamed skin lesions topped with silvery white scales. This type of psoriasis can assume many different appearances based on its location, the activity of the disease, and the treatment being administered. Plaque-type psoriasis is most commonly found on the elbows, knees, scalp, sacrum, umbilicus, intergluteal cleft, and genitalia (Camisa 56).
Guttate psoriasis is characterized by small dot-like lesions. Guttate psoriasis is the most common cause of psoriasis in children and young adults who have a prior history of upper respiratory infection, pharyngitis, or tonsillitis (Camisa 64). The lesions are not as scaly as plaque-type psoriasis and are likely to be found on the trunk and involve the face (Camisa 64).
Pustular psoriasis is characterized by pustules, which are blister-like lesions of non-infectious fluid, and cause intense scaling. Individuals with pustular psoriasis are often among the most seriously ill and may have to be hospitalized (Camisa 67).
Erythrodermic psoriasis is the rarest form of psoriasis and is characterized by intense redness and swelling, exfoliation of dead skin, and pain. Erythrodermic psoriasis usually develops during the course of chronic psoriasis. However, in some cases erythrodermic psoriasis is the first manifestation of psoriasis, even in children (Camisa 74). Individuals with this type of psoriasis may experience chills and low grade fever, and may be rather uncomfortable (Camisa 75).
Inverse psoriasis is characterized by smooth inflamed lesions in the body folds -- armpits, under the breast, skin folds of the groin, buttocks, and genitals.
Koebner's Phenomenon psoriasis are psoriatic lesions which appear at the site of injury, infection or other skin psoriasis, or may be a new lesion in an existing case.
The degree of psoriasis can also vary from individual to individual. It ranges in severity from mild (affects less than 2% of body) to moderate (affects 2-10% of body) to severe (affects greater than 10% of the body). Skin injury and irritation, sun exposure, diet, stress and anxiety, medications, and infections have been known to make psoriasis worse.
