Causes of Psoriasis
There are many beliefs as to the cause of psoriasis. Although no one knows for sure, many scientists believe that a biochemical stimulus triggers the abnormally high skin growth which will in turn cause the skin lesions. Heredity also plays a role in the development of psoriasis.
Because psoriasis is a lifelong condition, the levels of its severity and improvement can fluctuate over time. Psoriasis is not a contagious skin condition. Instead, an individual has a genetic predisposition for psoriasis, which can be activated by certain environmental factors or emotional stress. Individuals with psoriasis may find that their condition tends to flare up due to stress, certain medications, winter weather, and infections. Most often psoriasis affects the scalp, knees, elbows, hands, and feet.
Types of Psoriasis
Plaque-type psoriasis normally is referred to as psoriasis vulgaris. Plaque-type psoriasis is characterized by a rash patch of dry scaley skin that is inflamed and itchy. 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.
Guttate psoriasis is very common and usually has the appearance of small elevated papules that are inflamed with small red dots like appears much like chicken pox. Many of those with guttate psoriasis have had respiratory problems in the past or other infections in the esophagus or respiratory areas such as a tonsil infection. The areas most affected are the front and back upper torso and the face.
Pustular psoriasis is very rare but can be serious with hospitalization being possibly required. The pustules are non bacterial blisters but with severe scales.
Erythrodermic psoriasis is extremely rare and has the appearance of swollen skin that is very painful with a large amount of redness dry dead skin that is exfoliating or peeling off. 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. The severity of this erythrodermic psoriasis could have a low grade fever and will need a dermatologist care as the patient can have pain.
Inverse psoriasis is usually at the areas such as the inside of the elbows, or below the breast or any area where there is abrasion or chaffing of the skin. Also it can be located in the upper areas of the inner thighs, buttocks and groin areas.
Koebner Phenomenon psoriasis results from a small injury or trauma to the skin with resulting psoriastic lesions. Sometimes infections can occur.