TUESDAY, April 25, 2023 (HealthDay News) — Skin conditions may be the first sign that a person has a rheumatic disease that will also affect the joints, muscles or ligaments.

It’s essential to know what to look for, said Dr. Kathryn Dao, an associate professor of internal medicine in the Division of Rheumatic Diseases at UT Southwestern in Dallas.

“Skin lesions can occur at any time,” Dao said in a university news release. “If they are associated with an autoimmune disease, they will manifest when the disease is active. When autoimmune diseases are treated, the skin lesions will usually improve.”

People should see their doctors if their skin lesions are painful or if they are combined with other symptoms, such as fever, weight loss, diarrhea or joint swelling. It is fine to monitor skin conditions to see whether they resolve on their own if there are none of these other symptoms, Dao said.

“If the lesions progressively get worse, patients should try to get in to see their doctor sooner for an evaluation,” she said.

Dao said it’s important to avoid scratching skin lesions, which may worsen or cause an infection. She also urged people to protect themselves from the sun and get regular skin checks.

Dao and colleague Dr. Benjamin Chong, an associate professor of dermatology at UT Southwestern, highlighted some common skin problems that they say could foretell of a serious rheumatic condition.

Photosensitivity can be an early symptom of systemic lupus erythematosus (SLE) or dermatomyositis, a rare disease that can cause muscle weakness and skin rashes. Direct sun or ultraviolet light exposure could damage the skin, they said.

Sun exposure may produce rashes, including those that are located on the bridge of the nose and cheekbones in those with SLE.

Some lesions might look like ringworm with rough, red patches. This can signal subacute cutaneous lupus. Damage, such as scarring, hair loss, and lighter and darker skin, could be permanent in cases of discoid lupus.

Redness and itching might appear over the scalp, chest, neck, eyelids, hands, arms and other areas exposed to the sun with dermatomyositis. Patients may also have thickened, red plaques on the knuckles. It’s important to use sun protection when outdoors, including wearing hats, long-sleeved shirts and pants.