How Lupus Affects the Kidneys

Lupus is an autoimmune, chronic inflammatory disease that is caused by the immune system attacking your own tissues and organs. The inflammation associated with lupus can affect all different parts of the body such as the kidneys, brain, heart, joints, lungs, and skin. The severity of lupus can range from being mild to life-threatening. While there is no cure for lupus, there are treatment options available that can manage the symptoms and allow you to go on about your normal life. In the U.S., there are about 1.5 million people living with lupus and each year, more than 16,000 new cases are diagnosed. Globally, there are at least five million people with lupus.

Lupus can affect any part of the body, but most often the kidneys, joints, skin, heart, lungs, blood, or brain. Lupus can affect the renal system. The renal system is composed of the two kidneys, as well as two ureters, the bladder, and the urethra. The kidneys are the primary organs within the renal system and are responsible for maintaining the correct amount and type of body fluids, removing waste products and toxic substances, and regulating the hormones that help control blood pressure and blood volume.

Risk factors for lupus:

• Being female 

o While lupus can affect both men and women, women are affected most. 

o In fact, 90 percent of people who are diagnosed with lupus are women. 

• Age

o People between the ages of 15 and 44 are most likely to develop lupus. 

• Race

o Lupus is more common if you are African-American, Hispanic/Latino, and Asian. 

So how does lupus affect the kidneys? Lupus affects the kidneys through a condition called lupus nephritis. This occurs when the nephrons become inflamed. The nephrons are structures within the kidneys that filter the blood. When the nephrons become inflamed, this is called glomerulonephritis, or nephritis. Lupus nephritis caused by lupus leads to inflammation of the kidneys. This causes the kidneys to be unable to remove waste properly from the blood or control the amount of fluids in the body.

When abnormal levels of waste build up in the blood, this can cause edema, or swelling. If this condition is left untreated, nephritis can cause scarring and permanent damage to the kidneys. It can also potentially cause end-stage renal disease. People with end-stage renal disease need to be treated with dialysis, which is regular filtering of the body’s waste. They may also need a kidney transplant so that at least one kidney is working properly.

People with lupus who are at risk for lupus nephritis most often develop the condition within the first five years after the symptoms of lupus start. Lupus nephritis usually affects people between the ages of 20 and 40. When lupus nephritis is in its early stages, there often little to no symptoms that a person will experience. If symptoms do occur, they often include weight gain, swelling in the feet, ankles, legs, hands, and/or eyelids. The swelling usually becomes worse throughout the course of the day. Another symptom a person may experience is foamy urine which may appear red in color. 

Here are some tips to help protect your kidneys, especially if you suffer from lupus and/or lupus nephritis.

• Exercise regularly.

• Limit cholesterol.

• Drink enough fluids to stay well hydrated.

• Eat a low-sodium diet, especially if hypertension is an issue.

• Avoid medications that can affect the kidneys, such as nonsteroidal anti-inflammatory drugs (NSAIDs).

• Maintain a healthy blood pressure.

• Avoid smoking and drinking alcohol.