Physicians usually diagnose psoriasis by visual inspection.
This involves the information of the skin, scalp, fingernails and toenails for reddening or scaling skin that is characteristic of psoriasis.
Small pits on the fingernails are also signs of psoriasis.
A skin biopsy, or scraping and culture of skin patches, may be needed to rule out other disorders.
A skin biopsy, or scraping and culture of skin patches, may be needed to rule out other disorders.
In psoriasis, the examination will usually show proliferation of dry skin cells, but may not show signs of inflammation. Changes in the nails are often strong indicators of psoriasis.
If joint pain is present, an x-ray may be used to check for psoriatic arthritis.