How do you diagnose discoid lupus erythematosus?
Diagnosis of DLE usually requires a skin biopsy. A small sample of a discoid lesion is removed, specially prepared, and examined under a microscope. Usually, the lesion has certain microscopic characteristics that allow it to be identified as a DLE lesion. Blood tests will not reveal the type of antibodies present in SLE, and physical examination usually does not reveal anything other than the skin lesions. If antibodies exist in the blood, or if other symptoms or physical signs are found, it is possible that the discoid lesions are a sign of SLE rather than DLE. Source: The Gale Group. Gale Encyclopedia of Medicine, 3rd ed.
