Psoriasis is a common skin disorder worldwide. It is estimated that about 0.1% to 3% of people around the world suffer from psoriasis. Psoriasis affects all races, sexes, children, men and women.
Psoriasis is an inflammatory skin condition characterized by red, scaly patches of skin. There are several clinical types of psoriasis:
- Plaque psoriasis (the most common type): raised, thickened patches of red skin covered with silvery-white scales; commonly seen on the scalp, knees and lower back
- Pustular psoriasis: small pus-filled blisters with surrounding redness and swelling of the skin; May be localized to the palms or soles.
- Erythrodermic psoriasis: Generalised red, swollen, scaly skin– often a preventable complication of untreated or improperly treated psoriasis.
- Guttate psoriasis: small, drop-like, scaly lesions over the body, seen commonly in children and young adults
- Flexural psoriasis: smooth red lesions in the folds of the skin, commonly seen in groins, armpits and under the breast.
- Palmo-plantar psoriasis: Red, scaly patches of skin affecting the hands and feet only, and commonly mistaken for hand and feet eczema
- Scalp psoriasis: Psoriasis may be localized to the scalp, where it causes profuse dandruff. A proportion of these may develop into psoriasis elsewhere after years.
- Psoriatic Arthritis: In addition to the skin, psoriasis can also affect the nails and joints.
What causes Psoriasis?
Psoriasis appears to be multi-factorial. Many have inherited genes that make them more prone to develop psoriasis, however, other factors appear important in triggering the onset of psoriasis. Known aggravating factors that can trigger psoriasis flare up are: stress, injury, irritation, infection, climate, hormonal change, drugs, obesity, alcohol and smoking.
Can psoriasis affect other parts of the body, apart from the skin?
Yes, psoriasis is increasingly being recognised as a chronic inflammatory disease that is more than skin deep. Between 15% to 40% of sufferers may develop inflammation of the joints or arthritis, which is progressively destructive in nature. The risk is higher in those with a family history of psoriatic arthritis or who have nail psoriasis. Psoriasis sufferers also have a higher chance of developing diabetes, high blood pressure and heart disease.
The most common treatments are topical medications, phototherapy, photochemotherapy (PUVA), and oral or injectable medication (for moderate to severe psoriasis, or when joints are involved). Biologics injections such as ustekinumab and adalimumab, which may be self-injected, are the newest treatments available for severe psoriasis not responding to conventional therapy, or when patients have unacceptable side effects to conventional therapy. Oral or injected steroids are best avoided as they can cause unstable psoriasis and severe flares when the steroids are withdrawn. It is best to consult a dermatologist for extensive psoriasis or psoriasis not responding to first-line cream treatments, as psoriasis is a chronic problem and treatment efficacy has to be balanced against long-term side effects of treatment.