Psoriasis is a disease of the skin that is believed to be caused by a faulty response of the immune system. According to the National Psoriasis Foundation, the immune system sends out instructions to the skin cells to reproduce. When they reproduce too rapidly, they build up, causing thick, irritated areas of skin. The different types of psoriasis have some unique signs and symptoms.
Plaque Psoriasis
Plaque psoriasis is the most common type of psoriasis. Signs of plaque psoriasis are patches (plaques) of skin that are raised up, dry, red and scaly. These patches of skin can develop on any part of the body and be tender to the touch, as well as itchy. According to the Mayo Clinic, you could develop only one plaque or several in different areas of the body.
Guttate Psoriasis
With guttate psoriasis, instead of large areas of plaque patches, there are small, red, teardrop-shaped spots that can appear on the body. It is not as common as plaque psoriasis, and the National Institutes of Health state that it is most often diagnosed in patients under 30 years of age and often after battling an infection. Along with the tear drop spots on the body, signs of guttate psoriasis are itching and silvery flakes that are on top of the red spots.
Pustular Psoriasis
Pustular psoriasis is another uncommon type of psoriasis. The signs of it begin as red patches of skin, and then on these patches white blisters filled with pus will appear. After the blisters appear, they can scale over. The National Psoriasis Foundation reports that pustular psoriasis can develop over one part of the body, such as fingers and toes or over the torso and other areas. It can develop or be triggered by many factors such as pregnancy, medications, UV light or even stress.
Erythrodermic Psoriasis
The Mayo Clinic lists erythrodermic psoriasis as the least common type. Signs of it are a large body rash that is red and then peels. It can have a burning or tingling sensation. Like pustular psoriasis, it can be ignited by sunburn, medications, steroids or even another type of untreated psoriasis.
Inverse Psoriasis
Inverse psoriasis can often be mistaken for simple skin irritation. Signs are patches of skin that are red and smooth and occasionally shiny in appearance. It is found in the folds of the skin in areas such as the groin or armpits or in obese people that have deeper skin folds. The rubbing of the skin can cause irritation, and occasionally the patches can become sore and painful. Due to the overlapping skin and its lack of exposure to air, the skin can also be prone to bacterial infection.
Most types of psoriasis, except for inverse psoriasis, can also spread to the nails or the scalp, causing "scalp psoriasis" or "nail psoriasis." According to the Mayo Clinic, it can also cause problems brought on by inflammation, such as arthritis in the joints and conjunctivitis in the eye.
