Systemic lupus erythematosus (SLE), an autoimmune disease, is truly a disease of symptoms. Its attacks on the body’s immune system can affect everything from the skin and joints to internal organs, like the kidneys. When lupus affects the kidneys, it is called lupus nephritis (LN).
For the most part, kidney problems in lupus are from damage to a part of the kidney known as the glomerulus.
People who have lupus and associated glomerular damage have lupus glomerulonephritis (LGN). There are several types of lupus glomeruloneprhitis that vary in their severity and are detected by biopsy. LGN occurs when antibodies and complement proteins build up in the kidneys and cause inflammation. Biopsy of the kidney is used to identify the type of LGN, which helps predict the expected course of kidney problems. LGN is divided into six different types based on the biopsy.
About one-third of those who suffer with SLE will encounter some kind of lupus nephritis.
Symptoms and signs, of which there are very few, include:
- Blood in the urine
- Foamy urine
- Frequent nighttime urination
- High blood pressure
- Inflammation and swelling elsewhere on the body, due to loss of protein in the urine (edema), usually the feet, ankles and legs
To determine that a patient has lupus nephritis, a physician will conduct urine tests, as well as a physical exam to check blood pressure and look for edema.
Once it is strongly suspected that a patient has lupus nephritis, the doctor will order a kidney biopsy. This is used to determine treatment.
Since some types of LN can result in complete kidney dysfunction and dialysis dependence, biopsy results are necessary to shape the patient's care plan and help determine which therapy is necessary and how aggressive to be with treatment.
Since lupus nephritis is not preventable, treatment will be used to improve kidney function. There are a few options available, and most likely your treatment will be individualized based on the severity and other factors of your disease. Some treatments include:
Diet: Changes in diet, to eliminate items like salt, proteins and excess calories, are often prescribed.
Blood pressure: Maintaining healthy blood pressure is important. Certain medications, in particular ACE-inhibitors, or angiotensin-converting enzyme inhibitors, may be prescribed, considering they carry some benefits to the kidneys as well.
Medicinal: Corticosteroids or immunosuppressives may prove successful. Diuretics can be used to eliminate excess fluid (and reduce swelling).
Dialysis: To control symptoms of kidney failure.
Transplant: Though not recommended for those with active lupus.
Sources: Lupus Nephritis. Medline Plus. Collected January 2008.
Lupus and Kidney Disease. Lupus Foundation of America. Collected January 2008.
