Of note, patients with systemic lupus erythematous develop discoid lupus lesions with some frequency. Sun exposure triggers lesions in people with discoid lupus erythematous. He also identified discoid lupus erythematosus in Jackson. Finally, many patients with systemic lupus also develop discoid lupus lesions. The breed is listed among those commonly affected by Canine discoid lupus erythematosus. However, patients who present initially with discoid lupus infrequently develop systemic lupus. These patients have firm, nontender nodules with defined borders underneath their discoid lupus lesions. People with discoid lupus may exhibit thick, red scaly patches on the skin. Pulsed dye laser is also an effective treatment for patients with localized discoid lupus. It can be misdiagnosed for other conditions like psoriasis, discoid lupus, etc. Patients who develop discoid lupus in childhood also have their own sub-type of disease. Dogs and horses can also get discoid lupus. "Pyropia" species are red algae with a discoid holdfast and short stipe. "Ulva lactuca" is a thin flat green algae growing from a discoid holdfast. Species of "Phyllipsia" have apothecia that are saucer-shaped to discoid, thick-fleshed, and usually sessile.