What is lupus nephritis?

Lupus nephritis is inflammation of the kidneys caused by systemic lupus erythematosus (SLE), an autoimmune disease in which a misfiring immune system mistakenly attacks the body’s own organs. SLE can affect the skin, joints, kidneys, heart and brain but which organs are involved varies greatly from person to person. The causes of a misfiring immune system are not entirely understood. Infections, hormones, certain medications and genetic factors are suspected. Lupus is more common in adult women of childbearing age but does occur in children as well.

Symptoms

• High blood pressure
• Dark urine
• Flu-like symptoms
• Joint pains and aches
• Swelling (edema) of the legs, ankles, eyes and hands
• Weight gain, caused by water retention when the kidneys do not filter properly

Some people may have few and subtle symptoms or none at all in the early stages of the disease.

Diagnosis

• Urinalysis will show blood, protein or both.
• Blood tests will show if the kidneys' filtering capacity has decreased.
• Blood tests can also show certain types of antibodies that are elevated in people with autoimmune diseases, but some people with lupus may have normal antibody results.
• A kidney biopsy is the most definitive way to diagnose the nature and extent of the kidney damage caused by lupus.

Treatment

Depending on the test results and biopsy findings, doctors may prescribe immunosuppressive drugs that control the overactive immune system. Corticosteroids may be prescribed.

When to Call for Help

If your child has bloody or foamy urine, joint pains and aches, fever and fatigue, especially if accompanied by swelling of the face, hands and legs, talk to your pediatrician.