Lupus nephritis is a complication of systemic lupus erythematosus (SLE), an autoimmune disease that affects various organs in the body. Lupus nephritis occurs when the immune system attacks the kidneys, causing inflammation and damage to the kidney tissue. This can lead to impaired kidney function, including decreased urine output and accumulation of waste products in the blood.

Symptoms of lupus nephritis can include swelling in the legs, ankles, or feet, foamy urine, high blood pressure, and fatigue. Diagnosis is typically made through blood tests to check for antibodies associated with SLE, as well as a kidney biopsy to examine the kidney tissue.

Treatment for lupus nephritis often involves medications to suppress the immune system and reduce inflammation, such as corticosteroids and immunosuppressants. In some cases, dialysis or kidney transplant may be necessary if kidney function becomes severely impaired. It's important for individuals with lupus nephritis to work closely with their healthcare provider to manage the condition and prevent further kidney damage.