The variety of symptoms that lupus can bring on can make it tough to spot. Another reason the disease can be difficult to identify is that some of its most common symptoms — such as fatigue, headaches, joint pain, swelling, and fever — occur in a lot of other illnesses, too. Lupus can imitate rheumatoid arthritis, blood disorders, fibromyalgia, diabetes, thyroid problems, and more, according to the Lupus Foundation of America. (1) So what are the signs it might be lupus and not something else?

Most Common Signs and Symptoms of Lupus

Rash that develops after sun exposure Unexplained fever and pain Swelling and stiffness of joints Extreme or unexplained fatigue Headaches Hair loss Mouth or nose sores Raynaud’s syndrome (fingers becoming white or blue when cold)

One common early sign that can be indicative of lupus is a photosensitive rash, meaning a rash that develops in response to sun exposure, particularly on the face and upper arms, says Dr. Kramer. Other early symptoms are unexplained fever and pain, swelling, and stiffness of multiple joints. Complications such as inflammation of the lining surrounding the lungs or heart can also occur early on, he adds. If you notice these symptoms or a combination of these symptoms and they can’t be explained by another problem or illness you know you have, see your doctor to get them checked out. With early diagnosis and treatment, many of the symptoms of lupus and its complications can be managed, says Stuart D. Kaplan, MD, a rheumatologist at Mount Sinai South Nassau in Hewlett, New York. Here’s more information about the most common early signs of lupus, as well as later ones, to help you better identify and learn about symptoms that might indicate lupus. One main type of lupus, cutaneous lupus erythematosus, is limited to skin symptoms, including a rash and lesions. People with cutaneous lupus most commonly develop a discoid rash. It appears as round, raised, red patches and can cause scarring, Dr. Caricchio explains. “It’s often confined to small areas above the neck, such as the ears and scalp,” he says. The rash usually does not itch or cause discomfort. Another subtype of cutaneous lupus is subacute cutaneous lupus, and people with it will develop thick, scaly, red lesions that usually do not scar and do not itch. It gets confusing because some people with both of these forms of cutaneous lupus will only experience skin symptoms, while for others, lupus will progress to become systemic lupus, meaning it will affect other parts of the body, too. And it’s important to point out that people who are initially diagnosed with systemic lupus (or SLE) can also get lupus rashes. One of the common rashes that occurs in people with systemic lupus is a malar rash. It’s also called a butterfly rash; it spreads across the bridge of the nose and cheeks and is a telltale sign of the disease because its appearance is so distinctive, Caricchio says. A malar rash can be flat or raised. While it usually isn’t painful, it can itch and burn. (3) And the rash can show up on other parts of the body, including the arms, legs, and torso. People with lupus should know that most rashes, and sometimes other symptoms, are aggravated by sun exposure, so you’ll want to avoid it or use sun protection. It’s critical to talk to your doctor about skin rashes and lesions that you observe, as many are treated differently, and some can be signs that the disease is progressing or changing. You may need other treatments, too. (If you can’t get a quick appointment with your rheumatologist or dermatologist, take pictures of any new or worsening rashes and send them through to the doctor.) RELATED: Is It Systemic Lupus (SLE) or Another Type?

Fatigue

At least half of people with lupus experience fatigue. (4) Fatigue may be brought on by the disease itself or from associated depression, anxiety, lack of exercise, and problems with sleep. (5) Because people with lupus need to avoid sun exposure, they may have low levels of vitamin D, which can contribute to fatigue. Lupus treatments may also play a role. Fatigue is an important symptom to address with your doctor. Regardless of the underlying cause, fatigue can negatively impact quality of life.

Fever

Unexplained fever (a temperature of more than 100 degrees Fahrenheit) is another common sign of lupus. Sometimes fever is associated with a lupus flare. (6) And some lupus medications can increase the risk of infection, which can also bring on a fever. (7)

Sore and Stiff Joints

Inflammation associated with lupus can cause stiffness, swelling, pain, and warmth of the joints, most commonly in the fingers, hands, elbows, ankles, and toes. (8) Most people with lupus will experience joint inflammation at some point, says Caricchio. For many people, joint pain is one of the first symptoms of the disease that they’ll notice and report.

Headaches

People with lupus are twice as likely to have migraine-like headaches, compared with individuals without the disease. People with Raynaud’s syndrome are more likely to have these headaches. Headaches can also be caused by inflammation of the blood vessels in the brain, a condition called vasculitis, or by blood clots within these blood vessels, which can occur in some patients with lupus. (10)

Mouth or Nose Sores

Mouth or nose sores can form in about a quarter of people with lupus. Let your doctor know about any sores you notice, such as cold sores or herpes lesions. Herpes outbreaks may be more common in people taking immunosuppressive drugs used to control lupus.

Hair Loss

The inflammation of the skin associated with lupus can sometimes result in hair loss. Once lupus is treated, hair may grow back. But discoid rash may cause scarring on the scalp and permanent hair loss. (11) Some of the medications used to treat lupus may also cause the hair to fall out, though this is sometimes temporary. (12)

Lupus Nephritis

Lupus nephritis, inflammation of the kidneys, is one of the most common complications of lupus. (13) People with lupus nephritis are at a higher risk of developing end-stage renal disease, requiring dialysis or a transplant, says Kaplan. Symptoms of lupus nephritis include high blood pressure; swelling of the hands, arms, feet, legs, and area around the eyes; and changes in urination, such as blood or foam in the urine, needing to go to the bathroom more frequently at night, or pain or trouble urinating.

Blood Disorders

Lupus can cause problems with the blood, too, including anemia, or low red blood cell count. Anemia can cause symptoms such as weakness and fatigue. (14) Thrombocytopenia is another blood disorder that may develop, resulting in lower platelet counts. (Platelets are the cell fragments that help the blood clot.) Symptoms of thrombocytopenia can include bruising easily, nosebleeds, and petechiae, when the blood appears as red pinpoints under the skin. (15)

Atherosclerosis

Atherosclerosis, or clogging of the arteries, can develop in people with lupus. This can cause chest pain and raise the risk of stroke, heart attack, and heart failure. People with lupus nephritis may be at a greater risk of developing atherosclerosis, according to a study published in PLoS One. (16)

Pericarditis

Pericarditis, or inflammation of the sac that surrounds the heart, can be an early complication of lupus, says Kramer. Symptoms include a sharp pain in the chest and shortness of breath. Chronic inflammation can damage the heart tissue, making it more difficult for the heart to pump blood. (17)

Myocarditis

Inflammation of the heart, called myocarditis, can cause chest pain, says Francis Luk, MD, an assistant professor of rheumatology at Wake Forest School of Medicine in Winston-Salem, North Carolina. Other symptoms include unexplained rapid or irregular heartbeat, and heart failure is possible.

Pleuritis and Pleural Effusion

Inflammation of the lining surrounding the lungs, or pleuritis, can occur in people with lupus. This can cause symptoms such as chest pain and shortness of breath, says Dr. Luk. The pain can worsen when taking a deep breath, sneezing, coughing, or laughing. (18) Pleural effusion, or fluid around the heart and lungs, may also develop and can cause shortness of breath or chest pain, says Caricchio.

Central Nervous System Inflammation

Inflammation of the central nervous system can cause confusion, seizures, and psychosis, says Luk. It can contribute to an increased risk of depression, headache, and stroke, as well as problems with vision in people with lupus. (19)

Miscarriage and Preterm Labor

Women with lupus have a higher risk of miscarriage and preterm labor, says Kaplan. Pregnant women with lupus also have a higher risk of preeclampsia — a serious condition causing increases in blood pressure and protein in the urine — and signs that the kidneys and liver may not be functioning well. (20) If you have lupus and do get pregnant (or if you have lupus and are trying to get pregnant), see a high-risk maternal-fetal medicine specialist who has expertise in how to best handle such pregnancies. Be sure to talk with your rheumatologist well in advance of trying to get pregnant.