Although psoriasis is a very common condition, answering the question ‘what is psoriasis’ can prove difficult as it shares features with a number of other skin conditions. Skin irritation, itchiness (pruritis), and redness are major psoriasis symptoms, along with the development of thick, flaky skin tinged with red patches and silvery-white scales. The appearance of psoriasis, in pictures, or when encountering someone suffering from psoriasis may lead some people to believe that the condition is contagious, but psoriasis cannot be spread to others and is instead thought to be an inherited disorder affecting the skin’s processes of cell replication.

How Do You Get Psoriasis?

Normal skin cells grow at deep levels in the skin and migrate to the surface in a four week period, or thereabouts. People with psoriasis have an abnormally fast rate of skin cell replication and new skin cells may move to the surface of the skin within two weeks, rather than four. This is what can cause the psoriasis plaques or scaling as the skin fails to exfoliate at the same rate, leading to a build up of skin cells.

Who Gets Psoriasis?

Psoriasis symptoms may occur at any age but is commonly found in those between 15-35 and may be triggered by stress on the immune system or where systemic inflammation occurs. The body’s immune system may mistake normal skin cells for foreign invaders and attack those cells, causing inflammation, itchiness, pain, and an increased rate of growth as skin cells try to replace themselves. Meanwhile, the skin cells killed by the abnormal immune response accumulate on the skin and create the classic picture of psoriasis.

What Causes Psoriasis?

Several things are thought to trigger psoriasis, although they are not causes of psoriasis as such. Flare-ups may occur where a patient has a bacterial or viral infection, following an injury to the skin such as a cut, bite, burn, or graze, or where the patient lives in a dry climate or suffers from dry skin. Psoriasis may also be made worse by some medicines such as those used to treat malaria, high blood pressure (beta-blockers), and depression (lithium). Patients experiencing stress, with little sun exposure, or sunburn, and those drinking excessive alcohol are also more likely to experience a psoriasis flare-up.

Unfortunately, those with autoimmune conditions or with weakened immune symptoms are more likely to suffer from severe psoriasis, and patients who have AIDS, rheumatoid arthritis, systemic lupus erythematosus, or those undergoing chemotherapy during cancer treatment may notice an exacerbation of their psoriasis symptoms. Psoriasis is also increasingly being linked to depression and stress, with some research finding a connection to the levels of serotonin transporter protein (SERT) in the skin.

Although psoriasis is a skin condition affecting the scalp, hands, face, and other areas of the body, around a third of patients may develop a type of arthritis called psoriatic arthritis which can be extremely painful and debilitating. The flare-ups that occur with skin psoriasis can also occur with joint psoriasis as inflammation comes and goes in the body.

Psoriasis symptoms and diagnosis

Psoriasis symptoms usually include marked patches of red, scaly, and irritated skin, often on the knees, elbows, and the torso (trunk), other areas may be dry, cracked, or appear normal and like healthy skin.

Scalp psoriasis is also fairly common and can cause sufferers to feel self-conscious regarding dandruff, with many psoriasis shampoos marketed to treat the condition. Skin psoriasis may create pruritic (itchy) spots with scales, thickened skin, and a silvery or pinkish-red colour.

Types of Psoriasis – Guttate and Plaque

There are a number of types of psoriasis, with psoriasis symptoms varying across these types. As such, the types are largely descriptive, with plaque psoriasis the most common. In plaque psoriasis, the skin is covered with flaky, silvery scales over thickened patches of reddened, inflamed, and itchy skin.

Guttate psoriasis describes a skin condition where there are small pinkish-red spots on the skin. This differs from pustular psoriasis that causes blisters that are white in colour but encircled by inflamed, red skin. Erythrodermic psoriasis is a more severe condition characterised by large patches of very red skin that may spread across the back, a large portion of the scalp, or other area of the body.

Less Common Psoriasis Symptoms

In some patients, psoriasis can cause lesions to develop on the genitals (normally in males), joint pain as psoriatic arthritis develops, and nail psoriasis. Where the nails are affected, a patient may notice that their nails become thicker and develop discoloured areas (brown or yellow in hue), along with pitting or the nails and the possible separation of the nail from the nail bed.

Psoriasis and Dermatologists

Diagnosing psoriasis usually involves a physical assessment by an experienced practitioner such as a dermatologist. Occasionally, a patient may be sent for a skin biopsy in order to ensure that no other condition is responsible for the skin symptoms. Patients with skin psoriasis and joint pain may prompt a physician to consider psoriatic arthritis as a diagnosis and x-rays or other diagnostic imaging may be recommended.

Next: Psoriasis treatments

Also of interest: Psoriasis and Depression / Acne, Psoriasis and Depression – What’s the Link?