Lupus nephritis is a frequent complication in people who have systemic lupus erythematosus — more commonly known as lupus.
Lupus is an autoimmune disease. It causes your immune system to produce proteins called autoantibodies that attack your own tissues and organs, including the kidneys.
Lupus nephritis occurs when lupus autoantibodies affect structures in your kidneys that filter out waste. This causes kidney inflammation and may lead to blood in the urine, protein in the urine, high blood pressure, impaired kidney function or even kidney failure.
Signs and symptoms of lupus nephritis include:
- Blood in your urine
- Foamy urine (due to excess protein in urine)
- High blood pressure
- Swelling in your hands, ankles or feet
- High levels of a waste product called creatinine in your blood
As many as half of adults with systemic lupus develop lupus nephritis. Systemic lupus causes immune system proteins to damage the kidneys, harming their ability to filter out waste.