Psoriasis

Psoriasis is a chronic inflammatory condition that is thought to affect around 2% of the population in the UK and the USA. It was first distinguished as a unique diagnosis in the 19th century, prior to that it was often mistaken for other conditions such as leprosy (Franklin and Glickman, 1986). Since that time numerous different presentations have been identified with a wide range of morphological features. This has lead to questions about whether all these presentations are indeed the one disease that is called psoriasis, or a range of conditions with some similarities. From a histopathological point of view, it is not always possible to distinguish psoriasis from other chronic inflammatory conditions; this will depend to an extent on the time at which a biopsy is taken. Whilst the very typical clinical appearance allows experienced practitioners to reach the right diagnosis, effective treatment becomes the next challenge. This section will consider the biology of psoriasis and explore the various treatment options available and how their efficacy might be enhanced. Specific issues about coping with psoriasis and its impact on quality of life are discussed, with reference made to Psychological and social aspects of skin care where generic issues of skin disease and mental health are considered in detail.