Many things. Lupus can effect any organ, so many symptoms are possible with lupus. The most common are general symptoms of fatigue, malaise, low grade fevers, joint pain, and then specific organ symptoms such as rash, hair loss, arthritis, mouth ulcers, chest pain, breathing problems, lupus can be a very difficult disease to diagnosis because it has so many potential symptoms and presentations.
Fever. Lupus is chronic inflammatory disease that can affect any organ of the body, including the joints, skin, heart, lung, kidney, liver, intestines. It can cause fever, butterfly rash on face, rash anywhere, arthritis, mouth sores, weakness, headaches, skin sensitivity to sun/sunburns. There are characteristic laboratory tests that allow your rheumatologist to make the diagnosis and start treatmen.