What Is Lupus? Symptoms, Causes, Diagnosis, and Treatment

Lupus is an autoimmune disease — meaning the immune system doesn’t function properly and attacks a person’s own body by mistake — and it affects multiple organs throughout the body. In healthy individuals, the body produces proteins called antibodies to fight off foreign invaders, such as viruses, bacteria, and fungi.

But in people with lupus, antibodies can’t distinguish between foreign invaders and the body’s own cells and tissues. The current theory is that with lupus, these autoantibodies attack cells and tissues, causing inflammation, which can lead to arthritis, lupus rash, kidney damage, and other symptoms and health problems.

Lupus is “the epitome of an autoimmune disease,” says Stuart Kaplan, MD, a rheumatologist at Mount Sinai South Nassau in Oceanside, New York. “It’s the body fighting itself and making antibodies against one’s own cells.”

This lifelong, chronic disease has the potential to affect almost every organ system in the body, although not all systems are affected in any one person. The first thing patients need to know is that lupus varies in symptoms and severity from person to person, adds Dr. Kaplan. Some people have active disease while others have mild disease. It’s important to note that lupus is not contagious.

There are several types of lupus:

Systemic Lupus Erythematosus (SLE) About 70 percent of people diagnosed with lupus have this form, making it the most common. In some people, the disease is mild and may cause only rash and some joint pain, says Kaplan. In others, inflammation can lead to kidney damage (also known as lupus nephritis) or other complications, he says.
Cutaneous Lupus Erythematosus This form of lupus develops in the skin as a rash. The most common form of cutaneous lupus erythematosus is discoid — which refers to the appearance of a round, raised, red, and scaly rash that does not itch.
About 10 percent of discoid lupus patients can go on to develop SLE.
Drug-Induced Lupus Erythematosus (DIL) Some drugs can cause conditions very similar to lupus, resulting in symptoms such as rash, arthritis, hair loss, and fever. “Once medications are discontinued, the symptoms go away,” thus it is not SLE, says Roberto Caricchio, MD, a rheumatologist at UMass Memorial Health in Worcester, Massachusetts.
Neonatal Lupus Technically neonatal lupus is not a form of lupus. The condition is the result of autoantibodies passing from a pregnant woman with lupus (or related condition) through the placenta and to the baby developing in the womb, causing mostly temporary symptoms, explains Virginia Pascual, MD, the director of the Gale and Ira Drukier Institute for Children’s Health at Weill Cornell Medical College in New York City. Some infants are born with symptoms such as skin rash, liver problems, or white blood cell counts. But those symptoms disappear within a few months and leave no lasting effects.

Learn More About the Different Types of Lupus

“The vast majority of lupus patients at some point will have joint pain with inflammation, some form of skin rash, and fatigue,” says Dr. Caricchio. Other common symptoms include:

Fever
Headaches
Sun sensitivity
Low red blood cell counts (anemia)
Swelling of the hands, arms, feet, legs, and around the eyes (edema)
Mouth or nose sores
Hair loss
Blood clotting
Raynaud’s syndrome, in which the small blood vessels in the fingers and toes spasm, limiting circulation, especially in cold weather

It’s important to note that among patients with lupus, type, and severity of symptoms differ from person to person, and new symptoms can appear at any time.

“The vast majority of lupus patients at some point will have joint pain with inflammation, some form of skin rash, and fatigue,” says Dr. Caricchio. Other common symptoms include:

Fever
Headaches
Sun sensitivity
Low red blood cell counts (anemia)
Swelling of the hands, arms, feet, legs, and around the eyes (edema)
Mouth or nose sores
Hair loss
Blood clotting
Raynaud’s syndrome, in which the small blood vessels in the fingers and toes spasm, limiting circulation, especially in cold weather

It’s important to note that among patients with lupus, type, and severity of symptoms differ from person to person, and new symptoms can appear at any time.

The answer to what causes lupus? “We do not know,” says Caricchio. Research has yet to pinpoint the exact conditions or triggers that lead to the disease, he explains — “however, the condition appears to be multifactorial.”

Experts suspect that your genes, as well as other things you’re exposed to throughout your life, affect likelihood of you getting lupus:

Genetics Doctors and researchers believe a genetic predisposition may contribute to the development of lupus, says Kaplan. Dozens of genetic variations have been found to be associated with the disease, affecting who gets it and how severe those cases are.
That means the disease is hereditary, making parents more likely to pass it to their children. But just because you are genetically predisposed to the condition, doesn’t necessarily mean you’ll get it.
Environment Researchers suspect environmental factors may increase the risk of developing lupus. For example, exposure to sun can cause a lupus rash and some systemic lupus activity, says Stacy Ardoin, MD, a clinical associate professor of internal medicine in rheumatology The Ohio State University Wexner Medical Center in Columbus. Other environmental factors that may contribute to lupus can include some drugs, viral infections, exhaustion, stress, and anything that can cause physical stress to the body (such as surgery, physical harm, injury, pregnancy, or giving birth).
Hormones Lupus is much more common in women than in men. One reason for this may be because of higher estrogen levels in women, notes Kaplan — though that has not yet been proven in scientific studies.

Learn More About What Causes Lupus

Diagnosing lupus “can be very challenging,” Dr. Ardoin says. This is because symptoms can range from a mild rash and arthritis to kidney failure and seizures — “with a whole spectrum in between.” Symptoms may mimic other diseases and conditions, such as infections or cancer.

To diagnose lupus, doctors will listen to the patient’s history and then perform a thorough examination. A history and physical exam consistent with the symptoms of lupus will prompt the doctor to conduct blood work to look for antibodies associated with the disease. For example, antinuclear antibodies bind to cell nuclei, damaging the cells or causing them to die. About 97 percent of people with lupus have these antibodies.

Other tests for lupus depend on the symptoms patients are experiencing, says Kaplan. For example, chest X-rays and echocardiograms may be necessary to investigate fluid around the lungs and the heart. If doctors suspect nephritis is present, the patient may need a kidney biopsy. Early diagnosis and treatment can help to avoid complications, he adds.

An accurate diagnosis of lupus can take time, says Caricchio. However, the availability of good lupus classification criteria can make the chance of receiving a wrong diagnosis slim, he adds. Classification criteria are a set of symptoms and signs doctors use after they suspect that you have lupus, to determine the type and severity of your case.

Doctors use two different systems to diagnose the condition: American College of Rheumatology criteria, published in 1997 and updated in 2019;

and another system, Systemic Lupus International Collaborating Clinics Classification criteria for systemic lupus erythematosus, or SLICC.

Fortunately, increased awareness among the general public and primary care physicians may mean patients may see a rheumatologist sooner rather than later for diagnosis, says Caricchio.

Learn More About How Doctors Diagnose Lupus and What Tests to Expect

Prognosis of Lupus

Up to 90 percent of patients will have a normal life expectancy if they are followed closely by their doctor and receive proper treatment.

Lupus can, however, increase mortality rates because patients have a higher risk of heart disease, infection, or complications such as inflammation of the kidney, or nephritis,

says Francis Luk, MD, assistant professor in the Wake Forest School of Medicine department of internal medicine.

While a lupus diagnosis can be overwhelming, if the disease is controlled, people living with the condition should be able to “go about life as normally as people who don’t have lupus,” Luk says.

Individuals should go on pursuing activities or hobbies they enjoyed before diagnosis, adds Caricchio. And, he says: Women with lupus can have children. “We don’t discourage having kids by any means,” he says. “But it is recommended that women become pregnant when lupus is not active, so that the chance of flare is minimal.”

Lupus is a chronic, lifelong disease. However, most people don’t experience symptoms continuously. Instead, there are different times when symptoms appear, known as lupus flares. How long flares last varies from patient to patient, but symptoms can typically persist from a few days to weeks at a time. “There’s no way to predict when a flare will occur,” says Dr. Luk.

Flare symptoms can also be wide-ranging. Some people may experience relatively mild flares that include rash and arthritis, while others have severe flares, such as kidney inflammation, adds Luk.

Rheumatologists typically manage lupus with a variety of drugs, says Caricchio, adding that treatment regimens are tailored to each patient based on his or her symptoms.

Medication Options for Lupus

Some patients with mild lupus — with a little joint pain or rash — can be managed with anti-inflammatory drugs such as nonsteroidal anti-inflammatory inhibitor drugs (also known as NSAIDs), says Kaplan. Steroids may also help with inflammation associated with lupus, he says.

Other drugs used to treat lupus include the antimalarial drug hydroxychloroquine, which modulates the immune system, and targeted medications including anifrolumab and belimumab, which are biologic medications (meaning they are made from natural sources). Some chemotherapy drugs and transplant drugs may be used, too, to treat patients with lupus nephritis or other organ problems, says Caricchio.

Why Lupus Monitoring Is Important

While lupus is more treatable than it used to be, the disease can still be life-threatening, Ardoin notes. “It’s hard to predict the course of illness, so it’s important for patients to check in regularly with their rheumatologist,” she says.

After people are diagnosed and begin treatment, they need to see their rheumatologists regularly for blood draws to monitor blood counts, systemic inflammation, and disease activity.

Blood tests also help doctors monitor levels of complement proteins, which boost the body’s immune response to infections. (Levels of complement proteins, as well as some others, are low when the disease is active, explains Ardoin.)

Blood and urine tests are also needed to check kidney function. “It’s important to regularly follow up with a rheumatologist to make sure the disease is not starting to become more severe,” says Luk. If kidney problems are not detected early, the risk of renal failure and death are higher.

Alternative and Complementary Therapies

In addition to treatment, certain lifestyle and dietary adjustments can help people with lupus. There’s no specific “lupus diet” but incorporating foods that fight inflammation can be beneficial. Maintain a healthy balance of fresh vegetables such as dark leafy greens, whole grains, and protein from fish and beans, and watch out for sugar and unhealthy fats. Limit high-fat and processed foods. And, avoid alfalfa — it has substances that can activate your immune system.

Dietary changes may also be necessary depending on which medication you’re taking for your treatment.

Learn More About Treatment for Lupus

Prevention of Lupus Flares

There’s no known way to prevent lupus itself, but there are steps you can take to help prevent flares of symptoms. You can’t entirely predict when a flare will happen but it’s important to stick to your treatment and identify — and then avoid or reduce — triggers such as stress, infections, and sunlight.

Maintaining overall health is key, too. Because lupus is associated with an increased risk of cardiovascular disease, whether due to inflammation or genetics, maintaining a healthy lifestyle is particularly important, says Caricchio. He recommends getting enough sleep, maintaining a healthy body weight, exercising, and eating a nutritious diet.

Additionally, people with lupus should be mindful to avoid sun exposure as much as possible by wearing sunscreen and protective clothing, says Kaplan. A photosensitive rash can become worse in UV light.

Good social relationships and support groups can also be important for maintaining mental health, says Ardoin.

Learn More About Preventing Lupus Flares

Complications of lupus can include:

Nephritis, or inflammation of the kidney, which can be mild or severe
Fluid around the heart (pericardial effusion) and the lungs (pleural effusion), which can cause shortness of breath or chest pain
Blockages of the blood vessels leading to the brain, causing stroke
Inflammation of the heart, or myocarditis, which can cause chest pain and heart disease
Inflammation of the brain, which can cause confusion, seizures, and psychosis
Depression and problems with short-term memory
A higher risk of miscarriage and preterm labor in pregnant women
Long term cardiovascular effects

Lupus is diagnosed in about 16,000 people each year.

A total of 204,295 people had lupus in 2018 in the United States.
The study provided the first national estimate of how widespread the autoimmune disease is, including its prevalence in certain ethnic groups.

Previous work had estimated national rates but extrapolated estimates based on much smaller data sets.

The new research estimates that for every 100,000 people in the population, there were 72.8 cases of lupus. Lupus rates are nine times higher for women than for men, at 128.7 versus 14.6 per 100,000 people; and are highest among American Indian, Black and Hispanic women, at 270.6, 230.9, and 120.7 cases per 100,000 people respectively. There are 84.7 cases of lupus per 100,000 white women, in contrast.

Because the new study estimates that just over 200,000 Americans suffer from SLE, lupus might be officially reclassified as a rare disease under the U.S. Rare Diseases Act.
This shift could make drug development easier for pharmaceutical companies in search of potential lupus therapies.

A rare-disease classification would decrease the number of study participants needed for testing new treatments and shaping the design of clinical trials.

Lupus typically develops in people between 15 and 45 years old.
But pediatric lupus also occurs. Lupus in children tends to be more aggressive than in adults, says Dr. Pascual. The exact reasons for this are not understood. One theory is that people are born with a genetic susceptibility to the disease that may be triggered by environmental factors such as a virus. “Children with the condition may have inherited a more complex set of predisposing genes,” she says. But this theory has yet to be proved.

Children undergo the same diagnostic testing as adults, and treatments are similar. “There are few clinical trials in children, so there is no option but to treat children based on the adult experience. We use the same drugs,” says Pascual, with doses adjusted according to the child’s weight.

Doctors should closely monitor children for drug side effects. Steroids, for example, can delay growth and cause high blood pressure. Chemotherapy can make children more prone to infections, says Pascual. Fortunately, life expectancy in pediatric lupus has improved dramatically in the last 15 years, she says.

Ongoing research continually investigates new treatments for lupus, develops insights into better disease management, and examines the causes of the disease. A particular recent area of focus is the potential link between gut health and the development of lupus and disease activity.

While the medical establishment knew anecdotally about the steep disparities in the incidence of lupus, particularly affecting women from the Black, Indigenous, and People of Color (BIPOC) communities, the concrete data was very sparse before the latest research showing lupus rates are highest among American Indian, Black, and Hispanic women, according to the study’s senior investigator, Emily Somers, PhD, an associate professor of environmental health sciences and of internal medicine in rheumatology at the University of Michigan School of Public Health in Ann Arbor.

Previous research had estimated that in industrialized Western countries, people of African and Asian descent were two to four times more likely to develop lupus than people of European descent.

The data from Dr. Somers’s group was a first step into gathering more reliable, detailed data on the issue, using a standardized way of defining cases, Somers said. “It’s important to have a firm understanding of baseline rates of this disease to flag trends in the population and how they’re changing over time,” she said.

The research also quantified, for the first time, the prevalence of lupus in men with direct comparison between ethnic groups. Lupus rates are highest in Black men, followed by Hispanic, Asian, and white men.

Somers’s group, funded by the Centers for Disease Control and Prevention, continues their work by looking at why there are such stark disparities in lupus between genders and race. Using the data from the five registries, the researchers are also looking at patients’ experiences with lupus and how the disease evolves.

While lupus typically occurs alone, some people with lupus experience symptoms of other connective tissue diseases.
Common overlapping conditions include:

Celiac disease
Rheumatoid arthritis
Autoimmune thyroid disease

Lupus may also occur with the chronic autoimmune conditions myasthenia gravis and scleroderma; antiphospholipid syndrome, which encourages the formation of blood clots; polymyositis and dermatomyositis, which can cause swelling in the muscles and skin; and Sjögren’s syndrome, which affects moisture-producing glands in the eyes and mouth.

The Takeaway