Understanding Lupus Nephritis

Lupus nephritis, also known as kidney lupus, is a chronic condition that may affect people with lupus. While it isn’t the same same as chronic kidney disease (CKD), the kidney damage caused by lupus nephritis can require similar treatment and can lead to kidney disease in some cases.

What is lupus?

Lupus is a chronic autoimmune disease that causes the body’s immune system to attack its own tissues. Lupus can affect any part of the body, causing damage, inflammation, and chronic pain in whatever organs it targets. Lupus disease affects an estimated 1.5 million Americans and 5 million people around the world. Women make up 90% of lupus cases, and women of color have a higher risk than Caucasian women. In fact, African American women are two to three times more likely than Caucasian women to have it. There are several types of lupus—the most common is Systemic Lupus Erythematosus (SLE).

What is lupus nephritis or kidney lupus?

Lupus nephritis occurs when lupus affects the kidneys. In 60% of people with lupus, the disease attacks the filters in the kidney, called glomeruli. Lupus causes inflammation and scarring in the blood vessels that form these filters and can even attack the kidneys themselves. This condition is called lupus nephritis, which is sometimes referred to as kidney lupus. Much like CKD, lupus nephritis can cause symptoms and kidney damage that need to be managed. It can even lead to kidney failure.

What are the signs and symptoms of lupus nephritis?

Lupus itself can be hard to detect and diagnose, because most lupus symptoms could easily be attributed to other diseases. On average, it can take up to 6 years after initial symptoms before a person is diagnosed with lupus. Common symptoms of lupus may include:

Pain, swelling and stiffness in your muscles and joints
Unexplained fever of 100°F.
Intense or prolonged fatigue
Inflammation
Chest pain
Hair loss
Raised red patches or rashes on your skin
Butterfly-shaped rash on your nose and cheeks
Sensitivity to light
Ulcers in your nose or mouth

When lupus affects kidneys, symptoms can also be difficult to recognize. If you do notice any of the following symptoms of lupus nephritis, it’s important to alert your doctor:

Foamy urine
Blood in your urine
Swelling in your legs, ankles, or elsewhere due to fluid retention

How is lupus nephritis diagnosed?

There are several tests that doctors use when determining whether lupus is affecting your kidneys. This process can take time, especially if you don’t already have a lupus diagnosis.

Blood and urine tests are commonly used to check kidney function, though they can’t always explain what’s causing diminished kidney function. That means that if lupus is causing your kidney damage, it may take extra testing to verify. There are 3 tests commonly given:

A urine test will measure the amount of protein and blood in your urine. You’ll provide a urine sample, and your treatment team will use a dipstick to test the urine. The dipstick will change colors if it detects protein or blood. Elevated levels of either one is a sign that your kidneys aren’t working properly.
A blood test will help measure how well your kidneys are working. A simple serum creatinine blood test measures the amount of creatinine in your bloodstream. Creatinine is made when the body breaks down protein, and it usually gets removed by healthy kidneys. When kidneys aren’t working properly, creatinine builds up in the blood. Your doctor will calculate your estimated glomerular filtration rate (eGFR) using your serum creatinine level, along with weight, gender and ethnicity, to measure your kidney function. You may also get a separate blood test to check for certain antibodies that indicate the presence of lupus.
A kidney biopsy will help your care team understand whether lupus is causing the decreased kidney function. Using a CT scan or ultrasound to guide them, a doctor will take a small sample of your kidney so a pathologist in a lab can examine the piece to learn more. Studying the biopsy can help confirm the presence of lupus nephritis, the stage and how best to progress with treatment.

How is lupus nephritis treated?

There is currently no known cure for lupus. However, lupus and associated conditions like lupus nephritis can be managed with proper treatment. Lupus nephritis treatment will likely involve a rheumatologist (joint specialist) and nephrologist (kidney specialist) in addition to your other doctors. The goals of treating lupus are to:

Reduce inflammation
Manage the immue system response
Prevent flare-ups
Minimize pain and fatigue
Minimize damage to organs

People with lupus and lupus nephritis may take medications to manage their symptoms. Prescribed medications may include:

Immunosuppressant drugs and corticosteroids—to decrease your immune system’s response and help control inflammation. This is an important part of easing the effects of lupus.
Blood pressure medications—to help manage high blood pressure that may arise as a side effect.
Diuretics—to help relieve the fluid buildup from diminished kidney function.

Because lupus can target any part of your body and every case is different, this isn’t a full list of medications you may be asked to take. Your doctor may also recommend dietary changes to help decrease stress on your kidneys, including cutting back on salt and managing phosphorus.

Can lupus nephritis cause kidney failure?

Lupus nephritis can cause kidney failure, though it doesn’t always happen. Medications can also help keep lupus in check for years before lupus nephritis occurs. Early diagnosis and treatment are always helpful in minimizing the effects of lupus.

If lupus nephritis does cause kidney failure, it’s not a reflection on you or your treatment team. It’s possible for lupus to cause kidney failure even if you do everything “right.” What’s most important is proper treatment, and there are several treatment options to help you live well with kidney failure. Dialysis is an important and valuable option—and there are different methods of dialysis that may be right for you, including home dialysis or in-center dialysis. Right now, 468,000 people in the United States alone receive dialysis treatments. Another option is a kidney transplant. This transplant may come from someone you know, or from someone on a donor list. This important thing to remember is that it’s still possible to live well and thrive with renal failure.