Other fungi and psoriasis can produce similar changes, but the diagnosis can be established by looking at nail clippings under a microscope.
This enables them to biopsy areas where psoriasis will next appear.
Psychological stress, distress and disability in patients with psoriasis : consensus and variation in the contribution of illness perceptions, coping and alexithymia.
More work is required to determine whether the increased amount of these factors is specific to psoriasis.
The differential diagnosis is from contact dermatitis or psoriasis which can sometimes be difficult to distinguish clinically.
Psoriasis is thought to occur as a response to environmental triggers in genetically susceptible people.
Although the aetiology of psoriasis is unknown, understanding has increased over recent years.
Acitretin, the main metabolite of etretinate (a synthetic retinoid), is effective in some forms of psoriasis and has the additional benefit of a shorter half-life.