Final answer:
Discoid lupus is an autoimmune skin disorder that leads to chronic sores, primarily affecting parts like the face and scalp. It involves the immune system attacking the skin, in contrast to an allergy to pollen, which is an immediate hypersensitivity reaction.
Step-by-step explanation:
Discoid lupus is an autoimmune skin disorder wherein the immune system attacks the skin, leading to chronic, disc-shaped (discoid) sores, mainly on the face, ears, scalp, and sometimes on other body parts. These lesions can cause scarring if they heal without proper treatment. Discoid lupus is a chronic condition characterized by inflammation and the creation of lesions. It is distinct from systemic lupus erythematosus (SLE), which can affect any part of the body; however, some individuals with discoid lupus may eventually develop SLE.
Allergy to pollen, to contrast, is categorized as an immediate hypersensitivity reaction, not an autoimmune response. In an immediate hypersensitivity reaction, the immune system rapidly reacts to an allergen, such as pollen, rather than the body's own tissues. An autoimmune response would require the immune system to mistakenly attack and damage the body's own cells, as it occurs in autoimmune disorders like discoid lupus, systemic lupus erythematosus (SLE), and rheumatoid arthritis.
Overall, discoid lupus is a long-term autoimmune disorder affecting the skin, while allergies like pollen sensitivity involve immediate hypersensitive reactions to environmental antigens.