What is a common skin manifestation of systemic lupus erythematosus that patients may experience?

A common skin manifestation of systemic lupus erythematosus (SLE) is the butterfly rash, also known as a malar rash. This characteristic rash typically appears across the cheeks and bridge of the nose, resembling the shape of a butterfly. It is notable for its prominence in SLE and can be a key indicator in diagnosing the condition.

The butterfly rash often occurs during periods of disease activity and can be exacerbated by sun exposure, which is a common trigger for lupus symptoms. This rash is indicative of the photosensitivity often observed in patients with SLE and is part of the broader spectrum of symptoms that can affect various systems in the body.

In contrast, the other manifestations listed, while they may appear in different contexts, are not specific to SLE. Urticaria, which presents as hives, can occur in various allergic reactions, petechiae, small purple or red spots caused by bleeding under the skin, may indicate a different underlying condition, and squamous plaques are more typically associated with conditions like psoriasis rather than lupus.