Which skin manifestation is characteristic of systemic lupus erythematosus?

The butterfly rash is a well-known and characteristic skin manifestation of systemic lupus erythematosus (SLE). This rash typically appears as a red or purplish rash across the cheeks and nose, resembling the shape of a butterfly. It is one of the classic signs used in diagnosing SLE and is indicative of the autoimmune processes at play in the condition. The butterfly rash can be triggered by sunlight exposure, which is consistent with the photosensitivity often associated with lupus.

This distinctive patter helps differentiate SLE from other skin conditions. Conditions like psoriasis, eczema, and urticaria do not exhibit the specific butterfly-shaped distribution or are not as strongly linked to SLE's clinical presentation. Understanding this key feature is essential in recognizing and diagnosing systemic lupus erythematosus effectively.