What is Lupus Nephritis?

There are two primary types of kidney disease: acute kidney injury (single instances of lost kidney function) and chronic kidney disease (consistent loss of kidney function over three months or longer). There are a number of diseases that can lead to chronic kidney disease, and many of these originate elsewhere in the body.

One example of this is called lupus nephritis, an inflammation of the kidneys caused by systemic lupus erythematosus, or SLE. You may recognize the word “lupus”—this is a separate condition that affects the immune system and its ability to protect your body from disease.

 

Types of Lupus

Lupus is an autoimmune disease, which means it is caused by the immune system turning against the body and damaging organs and tissues. Lupus nephritis develops when the kidneys are damaged. Only SLE can cause lupus nephritis, and about 60 percent of all total lupus patients also develop lupus nephritis.

There are many types of lupus:

• Systemic lupus erythematosus (SLE): The most common form of lupus that affects everything from skin and joints to kidneys, the brain and other organs. It can be fatal if not treated correctly.
• Cutaneous lupus erythematosus: This form only affects skin and causes lesions and rashes on the body.
• Drug-induced lupus erythematosus: This a lupus-like disease that is caused by certain medications, most commonly Hydralazine, Procainamide and Isoniazid.
• Neonatal lupus: While not a true form of lupus, it affects the children of women who have lupus. Symptoms of neonatal lupus usually disappear several months after birth.

 

Lupus Nephritis Symptoms

The symptoms of lupus nephritis are different for everyone, and may not always show up right away—or at all. Some of them can include:

• Hematuria: Blood in the urine
• Proteinuria: Protein in the urine—one sign of proteinuria is foamy urine
• Weight gain
• High blood pressure
• Edema: Extra fluids that cause swelling in areas like the legs and ankles

 

Risk Factors

There are no known causes of lupus nephritis. However, there are a few factors that can increase your risk:

• Gender: Women account for about 90 percent of lupus cases
• Family history
• Infections or viruses
• Toxic chemicals or other allergens and pollutants

 

Tests and Treatments

Diagnosing lupus nephritis starts with a basic examination including a family history review, symptom assessment and a physical. Special tests are done to test for lupus nephritis:

• Urine test: This checks for blood and protein levels.
• Kidney biopsy: In this procedure, a small piece of kidney is removed and examined—this will determine which of the different types of lupus is present, and will help the doctor figure out which treatment to use.
• Blood tests: These check everything from protein and cholesterol levels to kidney filtering ability and antibodies.
• Ultrasound

If you have lupus nephritis, the main goal of treatment is to block the body’s immune system from continuing to attack itself. There are a few medications that are usually prescribed:

• Immunosuppressive drugs: These are meant to calm the immune system and are similar to medications used to treat cancer or prevent the rejection of organ transplants.
• Corticosteroids: This type of medication decreases inflammation.
• Diuretics: Diuretics help rid the the body of extra fluid and any swelling
• ACE inhibitors or ARBs: These are blood pressure medications that also help reduce protein loss.

 

Lifestyle Factors

There are a few habits that can help you prevent lupus nephritis, or manage symptoms if you do develop it. These include:

• Eat a diet that is low in sodium and cholesterol.
• Avoid smoking or drinking alcohol
• Exercise regularly
• Maintain a healthy blood pressure
• Stay away from nonsteroidal anti-inflammatory drugs, or other medications that can damage the kidneys
• Drink plenty of fluids

 

If you’re worried you might have some of the symptoms of lupus nephritis, speak to your doctor right away. Quick treatment can often help eliminate some of the worst symptoms, and can help you avoid a kidney transplant.

 

Are you concerned about your kidney function? Talk with your primary care physician about seeing a nephrology specialist.

 

Sources:

“Lupus and Kidney Disease (Lupus Nephritis).” National Kidney Foundation. https://www.kidney.org/atoz/content/lupus

“Lupus Nephritis.” WebMD. http://www.webmd.com/lupus/lupus-nephritis#1

“Are There Various Forms of Lupus?” Lupus Foundation of America. http://www.lupus.org/answers/entry/forms-of-lupus