• Posted September 23, 2025

Understanding Lupus: Symptoms, Risks and New Advances in Treatment

Systemic lupus erythematosus (SLE), often simply called lupus, is a chronic autoimmune disease in which the body's immune system malfunctions and mistakenly attacks its own healthy tissues and organs.

Lupus can involve almost every organ system, but it most commonly affects the skin, kidneys, joints and the linings of the heart and lungs. 

Types of lupus

Lupus can affect almost every organ system. Some patients only have skin disease, and this can be an intermittent rash that often flares during the summer months, as lupus is very sensitive to the rays of the sun. 

The rash of lupus can look like a sunburn on the face and upper chest, but can also be a deep, scarring rash (discoid lupus). The rash of discoid lupus can lead to permanent hair loss. 

Symptoms

Lupus can affect almost every organ system and, therefore, is often hard to diagnose. Additionally, lupus often isn’t the first condition that comes to mind with any of the symptoms a patient may have. 

It would be unusual for someone to present to a doctor suspecting lupus as a diagnosis, as it is more of a condition that explains multiple different symptoms and signs. 

It is a very difficult diagnosis to make without laboratory studies, as so many other conditions can cause similar symptoms, such as fatigue or heart or lung inflammation. 

• Rash: The most obvious symptom is a rash, usually worsened by sun exposure. The rash can cause scarring, so it is important to avoid sun exposure, even in the winter months. It could present as a severe sunburn in someone who hasn’t had sunburns in the past or as deep scars in the scalp, ears or face. A fever and rash could be many diseases, and infection should be ruled out before considering lupus. 

• Inflammation of the kidney, heart or lung: Inflammation of the lungs and heart is usually something that brings patients to an emergency room. Kidney involvement is usually found with lab testing, and patients are often asymptomatic.

• Blood clots: Blood clotting issues are usually dramatic and life-threatening, such as losing a pregnancy near term or developing blood clots to the lungs. These episodes are not usually diagnosed at home, but with special tests and imaging. 

• Joint pain: Some patients have a pattern of disease that overlaps with rheumatoid arthritis and is mainly swollen, tender joints and morning stiffness. Many patients are referred to rheumatologists with “pain all over,” and this is very unlikely to be due to lupus. The morning is usually the worst time of the day, with pain and stiffness improving as the day proceeds. 

• Mental health: Lupus causes issues with mental health and thinking, due to a cognitive impairment commonly known as “brain fog.” Symptoms include difficulty concentrating, struggling with complicated tasks like schoolwork and increased rates of depression and anxiety. This effect of lupus is not well understood.

• Blood disorders: Lupus can make the blood cell counts for red cells (anemia), white blood cells and platelets lower than expected. These are usually asymptomatic, but an important laboratory finding in making the diagnosis of lupus.

When to see a doctor about lupus

Lupus can cause a wide variety of symptoms. Rash is the most obvious sign, but it is not present in most patients. Other symptoms may include chest pain from inflammation in the heart or lungs; unexplained blood clots; arthritis at a young age; or unexplained kidney failure.

It can be difficult to diagnose lupus, since these symptoms have more common causes, and lupus is usually not the first diagnosis considered. 

How is lupus diagnosed? 

Lupus is often diagnosed after laboratory testing. Tests showing kidney problems, low blood cell counts and signs of inflammation are helpful clues. A test called the anti-nuclear antibody (ANA) is invaluable.

This antibody is found in many other diseases such as autoimmune liver disease, thyroid conditions and sometimes even healthy individuals, but it is always present in patients with active lupus. 

As such, a negative ANA excludes lupus as a diagnosis. Skin and kidney biopsies are also helpful for diagnosis. Not all patients will have all the symptoms and test results related to lupus, making diagnosis a challenge. 

Lupus can often be mistaken for an infection such as the flu, mononucleosis (“mono”) and pneumonia. The presence of a typical lupus rash often helps with making the diagnosis sooner, but the rash is not always present.

How is lupus treated? 

Several recent medical advances in lupus research have occurred, especially in drug development. Hydroxychloroquine is an important medication that almost every patient with lupus should take regularly.

It is safe and effective at treating many aspects of lupus such as arthritis, skin disease, hair loss and kidney disease. It can be taken during pregnancy and even during breastfeeding. 

One notable advancement is the development of anifrolimumab, a medication that targets the type I interferon pathway, which is overactive in many individuals with lupus. Anifrolimumab is a monoclonal antibody, a lab-created protein designed to mimic the body’s natural antibodies. This medication has shown promise in treating the skin manifestations of lupus.

Another exciting area of research involves CAR-T cell therapy, which uses a patient's      immune cells (T cells) to fight disease. This innovative approach, which has shown some success in certain blood cancers, is now being explored for autoimmune diseases like lupus. 

Multiple clinical trials, including one at Boston Medical Center, are underway to evaluate the safety and efficacy of CAR-T cell therapy in patients with severe lupus who haven't responded adequately to conventional treatments.

While still in the experimental phase, CAR-T cell therapy represents a potentially transformative treatment option for individuals living with lupus.

Causes of lupus 

The exact cause of lupus is unknown, but a combination of genetic, hormonal and environmental factors are thought to trigger the immune system to attack itself. However, a study in the journal Nature showed that one cause is a genetic mutation in a gene called “toll-like receptor 7.”

This mutation increased the chance that the immune system would be easily activated to attack healthy organs, even in the absence of infection. 

Risk factors 

• Sex: Women between the ages of 15 and 45 are much more likely to develop lupus and make up about 90% of all cases. 

• Family history: Having a sibling with lupus increases a person’s risk by about 20-fold compared to the general population.

• Race: People who are African American/Black, Inuit and Native American have triple the risk of lupus compared to white people, and their disease severity is often worse, especially kidney disease and the risk of death. Non-white Hispanic and Arab patients have about double the lupus risk compared to white patients in Canada and the United States.

Living with lupus 

Living with lupus can be challenging, but with the proper care and lifestyle adjustments, many people can lead full, active lives. Symptoms like fatigue, joint pain and skin rashes have treatments available to help manage discomfort and prevent flare-ups. 

It's important to work closely with your health care team, take medications as prescribed, and protect your skin from the sun. Even patients with dark skin who have never had issues with sunburns in the past need to use sunscreen regularly.

Sun exposure can trigger flares of the disease (including kidney disease) and cause scarring skin and scalp lesions (discoid lupus).  

Does lupus increase the risk of other diseases? 

Lupus can affect many body parts including the heart, kidneys and lungs. It can also raise the risk for infections, osteoporosis and cardiovascular disease. Some of these risks are related to the inflammation caused by lupus itself, while others may be linked to medications used to control the disease.

About the expert

Michael R. York, MD, is a rheumatologist at Boston Medical Center (BMC). Dr. York is also an assistant professor of medicine in the Department of Rheumatology at Boston University Chobanian & Avedisian School of Medicine. He has over 20 years of experience and is an expert in caring for patients with scleroderma (scleroderma), systemic sclerosis, morphea, lupus and psoriatic arthritis. Dr. York's research focuses on the role of the immune system on the development of systemic sclerosis, and other vascular and fibrotic diseases.