Psoriasis is an inflammatory disease of the skin characterised by an accelerated rate of epidermal turnover, with hyperproliferation and defective maturation of epidermal keratinocytes. In the majority of cases psoriasis is a chronic disease which, in its most common form -chronic plaque psoriasis - manifests itself as well-demarcated, often symmetrically distributed, thickened, red, scaly plaques. These may vary considerably both in size and in number and may involve any part of the skin, although they are found most typically on the extensor surfaces of the knees and elbows, in the sacral area and on the scalp. Appearances may be modified by the site of involvement, with flexural areas showing beef-red shiny plaques without scale (flexural or inverse psoriasis), palms and soles showing marked hyperkeratosis and fissuring, and nails becoming distorted by thimble-pits, thickening and nail-plate detachment. Up to 8% of people with psoriasis may have an associated inflammatory arthropathy,1 which in severe cases may be the dominant cause of morbidity.
Acute inflammatory forms of psoriasis may develop de novo or may complicate existing chronic plaque psoriasis. Acute guttate psoriasis characteristically affects children and young adults following streptococcal infection.2 Typically, showers of tiny red papules (likened to raindrops or guttae) erupt over large areas of the skin surface 1-2 weeks after an episode of acute streptococcal pharyngitis or tonsillitis. Erythrodermic and generalised pustular psoriasis are uncommon but severe and potentially life-threatening forms of psoriasis; they may be complicated by high-output cardiac failure, temperature dysregulation and septicaemia, particularly in the elderly.
Localised pustular forms of psoriasis, which may cause long-lasting disability, include chronic palmoplantar pustular psoriasis (palmoplantar pustulosis) and acropustulosis (acrodermatitis continua of Hallopeau). Only a minority of patients with these relatively uncommon variants have evidence of psoriasis at other sites3 and their relationship to ordinary psoriasis remains poorly understood.
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Do You Suffer From the Itching and Scaling of Psoriasis? Or the Chronic Agony of Psoriatic Arthritis? If so you are not ALONE! A whopping three percent of the world’s populations suffer from either condition! An incredible 56 million working hours are lost every year by psoriasis sufferers according to the National Psoriasis Foundation.