Psoriasis is a chronic disease of the skin that can cause scaling and inflammation. The clinical presentation varies depending on several factors, where some individuals may only have small localized scaly lesions and others have generalized, extensive scaly and pustular lesions. Aside from the skin, psoriasis also involves the joints, causing a condition known as psoriatic arthritis. If severe, psoriasis is potentially disabling.
Is this disease common?
Psoriasis affects one in every 50 people in the
. Its onset occurs at any age, although when occurring earlier suggest familial disease. United States
How is it diagnosed?
Since psoriasis may appear like other scaly forms of dermatitis (for example, seborrheic dermatitis), a skin biopsy may be necessary in order to get a definite diagnosis.
How does this disease appear?
Lesions in psoriasis are seen both on the skin and on the nails. Skin lesions have silvery scales with sharply defined borders between normal and affected skin. When the scales are removed, underneath it is glossy, reddish skin. Nail lesions are more varied, ranging from minor defects to grossly deformed nails.
What causes psoriasis?
External factors may act as triggers that cause psoriatic skin lesions. These factors include:
How is psoriasis treated?
Skin lesions found in psoriasis may be treated with topical or systemic medicines, with photochemotherapy or a combination of these therapies.
Topical treatments with some effectiveness include anthralin, vitamin D3, tazarotene, tar, topical glucocorticoids and skin emollients. Topical treatments are applied directly on the affected skin. They work by reducing inflammation, decreasing scale formation on the skin and in some cases causing skin to peel, leaving behind healthier skin.
Systemic treatments, on the other hand, include methotrexate, cyclosporine, retinoids, fumaric acid and systemic glucocorticoids. These are indicated for more extensive forms of psoriasis. However, there may be more side effects with systemic drugs compared to topical treatments.
Phototherapy works by exposing the skin to UV radiation, which kills inflammatory cells. This decreases inflammation and scaling of the skin.
Combination therapy, on the other hand, is preferable to monotherapy with topical, systemic or phototherapy treatments. Combination therapy offers faster relief at smaller doses of the drugs and with fewer adverse effects.