Lupus (systemic lupus erythematosus)

Lupus is an autoimmune disease. The immune system, which normally fights germs, attacks the body’s own tissues instead. Systemic lupus erythematosus is the most common type, and “systemic” means it can affect many parts of the body.

Lupus looks different from person to person. Some people have mostly skin and joint problems, while others have inflammation in the kidneys, blood or nervous system. No single test diagnoses lupus, so doctors combine symptoms, an exam and blood tests such as the antinuclear antibody (ANA) test.

The exact cause is not known. Experts think certain genes, together with things around us such as viral infections, sunlight, some medicines and smoking, can set it off. Problems with how the body clears away damaged or dead cells may also play a part.

Lupus can run in families, and having a relative with lupus or another autoimmune disease raises the risk. It is not contagious, so no one can catch it from another person. According to the US National Institutes of Health, women get lupus about nine times more often than men, and it most often starts between ages 15 and 45. In a 2021 study that pooled US lupus registries run with the Centers for Disease Control and Prevention, lupus was most common in American Indian and Alaska Native people and in Black people, followed by Hispanic people.

Common problems include painful, swollen joints, a “butterfly” rash across the cheeks and nose, and deep tiredness. Symptoms often come in flares, with calmer times in between. Sunlight can set off a flare in some people.

Lupus can also cause inflammation in the kidneys, called lupus nephritis, which can lead to kidney failure. It can lower blood counts, cause blood clots and affect the heart, lungs, brain and nerves. Which organs are involved shapes the treatment a person needs.

Lupus is usually lifelong, with ups and downs. Regular checkups with blood and urine tests help catch flares and kidney problems early. Warning signs of a flare can include more tiredness, joint swelling, pain, rash, fever, belly pain or headache.

Protecting the skin from the sun, staying active, managing stress and getting support can all help. Care also includes steps to prevent infections, bone thinning and heart disease. Patient groups offer education and support for people with lupus and their families.

For the few people who have a transplant, the process includes collecting stem cells, a hospital stay for high-dose treatment and a recovery period with a high risk of serious infection. It is done at centers experienced in treating autoimmune disease with transplants, often as part of research.

Lupus is not usually treated with a donor transplant. When a stem cell transplant is used for lupus, it is almost always autologous, which means the cells come from the person’s own body. No registry donor is involved, and no donor search is needed.

In their 2025 recommendations for adults, European transplant experts (EBMT) listed a donor transplant from a matched brother or sister as developmental for lupus, meaning more research is needed. They listed transplants from unrelated or partly matched donors as generally not recommended. For most people living with lupus, joining a donor registry is a way to help other patients rather than a need of their own.