Systemic Lupus Erythematosus (SLE)

Reviewed/Revised Feb 2023
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What is systemic lupus erythematosus (SLE)?

Systemic lupus erythematosus (lupus) is a long-term autoimmune disease. In an autoimmune disease, your immune system attacks parts of your own body.

  • Lupus is most common in women between the ages of 15 and 44, but it can happen to just about anyone

  • Joint and skin problems are common, but you may have problems with your kidneys, heart and lungs, brain, or other organs

  • Doctors may give you corticosteroids or other medicines that slow down your immune system

  • Lupus is a lifelong condition, but the earlier it's diagnosed, the better

What causes lupus?

In lupus your immune system attacks the connective tissue in your body. Doctors don’t know what causes this to happen.

Connective tissue is an important building block in the body. Connective tissue is in all your organs to hold them together. A problem with connective tissue can affect almost any organ in your body.

Sometimes, certain medicines cause lupus. If this happens, your symptoms usually go away when you stop taking the medicine.

What are the symptoms of lupus?

Symptoms can start slowly and build over time, or they can begin suddenly. Symptoms may come and go, sometimes disappearing for years between flare-ups.

Symptoms vary a lot depending on what parts of your body have been affected. Common symptoms for many people include:

  • Joint pain or swelling

  • Tiredness and feeling unwell

  • Fever

  • A red rash across your nose and cheeks, sometimes called a butterfly rash because it's shaped like a butterfly

  • Red rash on your neck, upper chest, or elbows

  • Worsening of rash when you're out in the sun

  • Raynaud syndrome (your fingers get pale, tingly, and numb when you get cold)

Symptoms that involve other parts of your body include:

  • Patchy hair loss

  • Dry eyes

  • Chest pain because of inflammation around the heart (pericarditis)

  • Trouble breathing

  • Headaches, problems with thinking, or mental disorders

  • Kidney problems and kidney failure

  • Feeling sick to your stomach or having diarrhea or belly pain

The following may cause your lupus symptoms to get worse or flare up:

  • Sun exposure

  • Pregnancy

  • Infection

  • Certain medicines

  • Surgery

How can doctors tell if I have lupus?

No one test can say whether you have lupus. Doctors use a set of criteria to say whether you have lupus. The criteria include a long list of:

  • Symptoms

  • Blood and urine test results

Instead of the criteria, doctors can also diagnose lupus based on:

  • A biopsy, in which doctors take out a piece of tissue from your kidney or skin to look at under a microscope

How do doctors treat lupus?

Doctors treat mild lupus with:

  • Sunscreen to protect skin from the sun

  • Corticosteroid creams to treat rashes

If your lupus is doing a lot of damage to your kidneys and other organs, doctors may have you take:

  • Corticosteroids

  • Medicine to keep your immune system from attacking your own tissue

If lupus has severely damaged your kidneys, doctors will treat you with:

You may need special care during pregnancy to keep from losing your baby, having your baby early, or having high blood pressure while you're pregnant. It's best to try to time a pregnancy for when you aren't having lupus symptoms.

Lupus increases your risk of getting infections, cancer, and other problems so it's important to see your doctor regularly over the long-term.

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