ETIOLOGY cause of the disease
Genetic factors – hereditary (commonly found that young people have inherited it) (Green 2011) If inherited there is a one in 4 chance of a sibling also inheriting the disease.

Environmental trauma – streptococcal infection, hiv, stress, smoking & alcohol (Watkins 2008) usually trigger the disease (Green 2011)

Drugs (medications) - may be exacerbated by lithium, beta-blockers, nonsteriodal anti-inflammatory drugs (NSAID), some antimalarial, and withdrawal of systemic steroids.

Sunlight- may occasionally aggravate – but usually improves it (Lui & Mamelak 2007) cited in (Watkins 2001)

The disease is distributed among men and women, with peak onset occurring at age 16-22 and 57-60 years. (Herrier 2011)

List the SYMPTOMS * Well-defined red scaly patches that may be covered in a silver scale, and may be itchy. These patches may present as isolated lesions or widespread and systematically distributed. They may appear anywhere on the body. The most common sites being the extensor surfaces of the elbows and knees or the scalp and some may coalesce to form large plaques. In some more acute cases the plaques may be inflamed, red and sore without the scale and silvery appearance.
Where precipitated by injury such as burns, cuts, grazes or surgical wounds, the psoriatic rash may appear at the site of the trauma. (known as the Koebner phenomenon). (Watkins 2011) * Hair loss may occur when scalp lesions came off (Wong & Rogers 2006) * Nails frequently show signs of pitting, onycholysis, subungual keratosis or