Lupus Nephritis & Your Kidneys
What is lupus nephritis?
Lupus nephritis is an inflammation of the kidneys caused by systemic lupus erythematosus (SLE). When you have lupus nephritis your kidneys are not doing a good job removing waste from your blood or controlling the amount of fluids in your body.
What causes lupus nephritis?
No one knows why some people with SLE develop lupus nephritis. Your family background and ancestry, medical conditions, and environmental factors such as exposure to chemicals or pollutants may all play a role in causing the disease.
Lupus nephritis usually gets worse over time, which can lead to kidney failure.
What is kidney failure?
Kidney failure is a serious condition that occurs when almost all (90%) of your kidney function is lost. If your kidneys fail, you will need to have dialysis or a kidney transplant.
Up to 3 out of 10 people with lupus nephritis will develop kidney failure within 15 years of diagnosis
What are the signs and symptoms of lupus nephritis?
A key feature of lupus nephritis is proteinuria, which means there are higher than normal levels of protein in the urine.
In the early stages of lupus nephritis, there are very few signs that anything is wrong. In fact, some people have no specific symptoms. Kidney problems can start around the same time lupus symptoms appear and may include:
- Foamy, bubbly or frothy urine
- Fatigue
- Inflammation or scarring of the kidneys
- Blood in the urine (hematuria): Your kidneys are supposed to stop blood cells from getting into your urine – if this occurs, your urine may look pink or light brown from blood
- Weight gain due to the fluid buildup in your body
- Swelling, usually in legs, feet or ankles
- Uncontrolled high blood pressure, which can lead to kidney damage
How is lupus nephritis diagnosed?
Lupus nephritis is diagnosed with urine tests, blood tests, and, if appropriate, a kidney biopsy.
Rheumatologists usually diagnose systemic lupus erythematosus and lupus nephritis and nephrologists confirm lupus nephritis with a kidney biopsy.
Explanation of Lupus Nephritis Classes
Lupus nephritis is divided into 6 different stages or classes based on the results of a kidney biopsy.
These classes are different from the stages of chronic kidney disease.
Some signs and symptoms associated with the different classes of lupus nephritis can be found in the table below.
Class 1
Class 2
Class 3
Class 4
Class 5
Class 6
How is lupus nephritis treated?
Lupus nephritis is often managed with immunosuppressants, chemotherapy and corticosteroids, also known as steroids, that suppress your immune system, antimalarial drugs, and blood pressure medicines to prevent damage to your kidneys.
The goals of treatment for lupus nephritis are to:
The goals of treatment for lupus nephritis are to:
Reduce inflammation in your kidneys
Decrease immune system activity
Block your body’s immune cells from attacking the kidneys directly or making antibodies that attack the kidneys
Will I need to change my diet?
When you are living with lupus nephritis, it’s important to pay attention to your diet. Eating the right foods may help you manage your kidney problems and also lower your blood pressure. Some kidney-friendly foods include:
- Foods with less salt and sodium
- Small portions of protein-rich foods such as chicken, fish, eggs, and beans
- Heart-healthy foods, such as lean cuts of meat, skinless poultry, beans, fruits, and vegetables
You may also be advised to eat foods with less phosphorus and potassium. High blood phosphorus levels can cause bone and heart problems. On the other hand, having high blood levels of potassium can also cause heart problems.
A registered dietitian nutritionist (RDN) can help you plan well-balanced meals and recommend healthy foods to eat.
What should I do next?
Living with lupus nephritis is challenging, but there are a number of things you can do to take an active role in your health and improve your wellbeing.
Most importantly, early diagnosis and treatment may help prevent long-term kidney damage. It’s also important to eat a low-sodium diet, maintain a healthy blood pressure, and exercise regularly. Speak with your healthcare team -- there may be other steps you can take to improve your condition.
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