Which symptom is a major manifestation of systemic lupus erythematosus?

The butterfly rash is a distinctive skin manifestation of systemic lupus erythematosus (SLE) and is often considered a hallmark symptom of the disease. Medically referred to as a malar rash, its characteristic appearance involves a redness that spreads over the cheeks and bridge of the nose, resembling the shape of a butterfly. This rash can be both a diagnostic indicator and a symptom of the underlying autoimmune condition, as it is associated with the inappropriate immune response that SLE entails.

While other symptoms such as joint pain, dry skin, and swollen lymph nodes can also occur in SLE, they are not as uniquely identifying as the butterfly rash. Joint pain is a common symptom in various inflammatory conditions, not exclusive to SLE. Dry skin can be seen in multiple dermatological conditions, and swollen lymph nodes may occur in various infections or immune responses. The butterfly rash, however, is particularly indicative of lupus itself. Thus, it serves a critical role in diagnosis and is closely tied to the essence of systemic lupus erythematosus.