Lupus is an autoimmune disorder affecting many parts of the body, such as skin, joints, brain, kidneys, blood cells, heart, and lungs. Lupus is formed when the immune system attacks the body's normal, healthy tissues.

In lupus the body's immune system cannot distinguish between foreign antigens and healthy tissues. This results in the immune system attacking and destroying even the healthy tissues, resulting in pain, swelling, and tissue damage. However, it is not clear about the exact cause of lupus.

The symptoms observed in individuals with lupus are:
Pain, stiffness, and swelling in the joints
Fever
Fatigue
Loss of appetite
Skin rash
Sensitivity to the sun
Swollen lymph nodes or glands
Breathlessness
Pain in the chest
Mouth ulcers
Dryness in the eyes
Headache
Confusion
Memory loss

Some factors responsible for increasing the risk of developing lupus include:
Genetic predisposition is seen in some ethnic groups such as African-American, Asian, or Hispanics
Hormones such as oestrogen
Environmental factors such as sun exposure and infections (by viruses like cytomegalovirus or Epstein-Barr virus)
Certain medications such as anti-seizure medicines
Stress

The organs affected by complications due to lupus are:
Brain and spinal cord
Eyes
Skin
Heart
Mouth
Reproductive organs
Blood and blood vessels
Lungs
Kidney
Organs in the gastrointestinal system
Muscles, joints, and bones