It is usually quite easy to diagnose, but there are no diagnostic blood tests. There are many mild cases, I think I have it. Our daughter, a dermatologist, is not certain either whether I do because it is very mild. Unfortunately, it can also cover the whole body. The disease came and went on father but never cleared despite the nasty smelling, sheet-staining, night time tar ointments he applied generously.
Psoriasis is a disease of unknown cause.
It's not contagious, but is likely to run in families. Triggers which can cause the scaly patches are cuts, scratches, severe sunburn, a strep throat, dried out winter skin and lithium or propranolol. Although there is no cure, a lot can be done to make patients feel better. Treatment can be tailor-made for age, disease, duration and extensiveness. Dry skin is counteracted by moisturizing creams.