Systemic Lupus Erythematosus (SLE)

Overview

Systemic lupus erythematosus, usually called SLE or simply lupus, is a chronic autoimmune disease. In autoimmune diseases the immune system, which normally protects the body from infection, mistakenly attacks the body's own healthy tissues. In lupus this misdirected attack causes widespread inflammation that can affect many different parts of the body, including the skin, joints, kidneys, heart, lungs, blood cells, and brain.

Because lupus can involve so many organs, its symptoms vary widely from person to person and can change over time. The disease typically follows a pattern of flares, when symptoms worsen, and periods of remission, when they improve or disappear. Lupus is most common in women of reproductive age, though anyone can develop it. There is no cure, but with modern treatment most people with lupus can control their symptoms, protect their organs, and lead full lives. Early diagnosis and ongoing care are key to good outcomes.

Symptoms

Lupus symptoms are highly variable and can affect almost any part of the body. Common features include:

• Fatigue, which is often severe and one of the most troublesome symptoms
• Joint pain, stiffness, and swelling
• A butterfly-shaped rash across the cheeks and nose
• Skin rashes that worsen with sun exposure
• Fever without an obvious infection
• Hair loss
• Mouth or nose sores
• Fingers and toes turning white or blue in cold or stress (Raynaud phenomenon)
• Chest pain when breathing deeply, headaches, or confusion in some cases

Kidney involvement is a serious aspect of lupus and may not cause symptoms until it is advanced, which is why regular monitoring is important.

Causes

The exact cause of lupus is not fully understood, but it is thought to result from a combination of genetic, hormonal, and environmental factors that lead the immune system to attack the body's own tissues.

• Genetics: certain inherited tendencies make some people more susceptible.
• Hormones: the disease is far more common in women, suggesting a hormonal influence.
• Environmental triggers: factors such as sunlight, infections, certain medications, and stress can trigger the disease or set off flares in susceptible people.

In most people no single cause can be identified; rather, several factors combine to tip the immune system toward attacking healthy tissue.

Risk Factors

Several factors increase the likelihood of developing lupus.

• Being female, especially during the childbearing years
• Age between roughly 15 and 45, when lupus most often begins
• A family history of lupus or other autoimmune diseases
• Certain ethnic backgrounds, in which lupus is more common and can be more severe
• Exposure to triggers such as sunlight, infections, or certain medications

Diagnosis

Lupus can be difficult to diagnose because its symptoms mimic many other conditions and vary widely. Diagnosis is based on a combination of symptoms, examination, and tests.

• Blood tests: including tests for antinuclear antibodies (ANA) and other specific antibodies, blood counts, and markers of inflammation.
• Urine tests: to check for kidney involvement.
• Clinical evaluation: reviewing the pattern of symptoms across the body over time.
• Organ-specific tests: such as a kidney biopsy or imaging when particular organs are affected.

No single test confirms lupus; doctors look at the overall picture and may use established criteria. Diagnosis sometimes takes time as the disease evolves.

Treatment

There is no cure for lupus, but treatment effectively controls inflammation, eases symptoms, prevents flares, and protects organs. Care is tailored to which parts of the body are affected and how severe the disease is.

• Antimalarial medicines: hydroxychloroquine is a cornerstone of treatment that reduces flares and protects organs.
• Anti-inflammatory drugs: NSAIDs for joint pain and inflammation.
• Corticosteroids: to control more significant inflammation, used carefully at the lowest effective dose.
• Immunosuppressants and biologic therapies: for more serious disease, especially when major organs such as the kidneys are involved.
• Sun protection and lifestyle measures: avoiding triggers and protecting the skin from sunlight.

Regular monitoring helps catch organ involvement early and adjust treatment over time.

Self-Care and Flare Prevention

• Protect your skin from the sun with sunscreen, clothing, and shade
• Take medications consistently, even when feeling well
• Get enough rest and pace activity to manage fatigue
• Eat a balanced diet and stay physically active as able
• Do not smoke, which worsens lupus and heart risk
• Manage stress and keep regular checkups to catch problems early
• Stay up to date on vaccines as advised, since infections can trigger flares

When to See a Doctor

See a clinician if you have persistent fatigue, joint pain, unexplained rashes, or other symptoms that suggest lupus, since early diagnosis improves outcomes. If you have lupus, contact your care team promptly during a flare or if you develop new symptoms. Seek emergency care immediately for:

• Chest pain or severe shortness of breath
• Sudden severe headache, confusion, seizures, weakness, or trouble speaking
• Signs of a serious infection, such as high fever, especially while on immune-suppressing medicine
• Significant swelling, very little urine output, or signs of kidney trouble

These can indicate serious organ involvement or infection that needs urgent treatment.

Related Topics

Frequently Asked Questions

References

1. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Lupus.
2. Mayo Clinic. Lupus — Symptoms and causes.
3. Centers for Disease Control and Prevention (CDC). Systemic Lupus Erythematosus (SLE).
4. MedlinePlus, U.S. National Library of Medicine. Systemic lupus erythematosus.