What Is Systemic lupus erythematosus / SLE / Lupus ?

Lupus is an autoimmune disease characterized by acute and chronic inflammation of various tissues of the body. Autoimmune diseases are illnesses that occur when the body's tissues are attacked by its own immune system. The immune system is a complex system within the body that is designed to fight infectious agents, such as bacteria and other foreign microbes. One of the ways that the immune system fights infections is by producing antibodies that bind to the microbes. Patients with lupus produce abnormal antibodies in their blood that target tissues within their own body rather than foreign infectious agents. Because the antibodies and accompanying cells of inflammation can affect tissues anywhere in the body, lupus has the potential to affect a variety of areas. Sometimes lupus can cause disease of the skin, heart, lungs, kidneys, joints, and/or nervous system. When only the skin is involved, the condition is called lupus dermatitis or cutaneous lupus erythematosus. A form of lupus dermatitis that can be isolated to the skin, without internal disease, is called discoid lupus. When internal organs are involved, the condition is referred to as systemic lupus erythematosus (SLE).

Both discoid and systemic lupus are more common in women than men (about eight times more common). The disease can affect all ages but most commonly begins from 20 to 45 years of age. Statistics demonstrate that lupus is somewhat more frequent in African Americans and people of Chinese and Japanese descent.

What are the symptoms and signs of lupus?
Patients with SLE can develop different combinations of symptoms and organ involvement. Common complaints and symptoms include fatigue, low-grade fever, loss of appetite, muscle aches, arthritis, ulcers of the mouth and nose, facial rash ("butterfly rash"), unusual sensitivity to sunlight (photosensitivity), inflammation of the lining that surrounds the lungs (pleuritis) and the heart (pericarditis), and poor circulation to the fingers and toes with cold exposure (Raynaud's phenomenon). Complications of organ involvement can lead to further symptoms that depend on the organ affected and severity of the disease.

Skin manifestations are frequent in lupus and can sometimes lead to scarring. In discoid lupus, only the skin is typically involved. The skin rash in discoid lupus often is found on the face and scalp. It usually is red and may have raised borders. Discoid lupus rashes are usually painless and do not itch, but scarring can cause permanent hair loss. Over time, 5%-10% of patients with discoid lupus may develop SLE.

Over half of the patients with SLE develop a characteristic red, flat facial rash over the bridge of their nose. Because of its shape, it is frequently referred to as the "butterfly rash" of SLE. The rash is painless and does not itch. The facial rash, along with inflammation in other organs, can be precipitated or worsened by exposure to sunlight, a condition called photosensitivity. This photosensitivity can be accompanied by worsening of inflammation throughout the body, called a "flare" of the disease.

Typically, this rash can heal without permanent scarring with treatment.

Most patients with SLE will develop arthritis during the course of their illness. Arthritis in SLE commonly involves swelling, pain, stiffness, and even deformity of the small joints of the hands, wrists, and feet. Sometimes, the arthritis of SLE can mimic that of rheumatoid arthritis (another autoimmune disease).

More serious organ involvement with inflammation occurs in the brain, liver, and kidneys. White blood cells and blood-clotting factors also can be characteristically decreased in SLE, known as leucopenia and thrombocytopenia, respectively. Leucopenia can increase the risk of infection and thrombocytopenia can increase the risk of bleeding.

Inflammation of muscles (myositis) can cause muscle pain and weakness. This can lead to elevations of muscle enzyme levels in the blood.

Inflammation of blood vessels (vasculitis) that supply oxygen to tissues can cause isolated injury to a nerve, the skin, or an internal organ. The blood vessels are composed of arteries that pass oxygen-rich blood to the tissues of the body and veins that return oxygen-depleted blood from the tissues to the lungs. Vasculitis is characterized by inflammation with damage to the walls of various blood vessels. The damage blocks the circulation of blood through the vessels and can cause injury to the tissues that are supplied with oxygen by these vessels.

Inflammation of the lining of the lungs (pleuritis) and of the heart (pericarditis) can cause sharp chest pain. The chest pain is aggravated by coughing, deep breathing, and certain changes in body position. The heart muscle itself rarely can become inflamed (carditis). It has also been shown that young women with SLE have a significantly increased risk of heart attacks from coronary artery disease.

Kidney inflammation in SLE can cause leakage of protein into the urine, fluid retention, high blood pressure, and even kidney failure. This can lead to further fatigue and swelling of the legs and feet. With kidney failure, machines are needed to cleanse the blood of accumulated poisons in a process called dialysis.

Involvement of the brain can cause personality changes, thought disorders (psychosis), seizures, and even coma. Damage to nerves can cause numbness, tingling, and weakness of the involved body parts or extremities. Brain involvement is referred to as lupus cerebritis.

Many patients with SLE experience hair loss (alopecia). Often, this occurs simultaneously with an increase in the activity of their disease. The hair loss can be patchy or diffuse and appear to be more like hair thinning.

Some patients with SLE have Raynaud's phenomenon. In these patients, the blood supply to the fingers and/or toes becomes compromised upon exposure to cold, causing blanching, whitish and/or bluish discoloration, and pain and numbness in the exposed fingers and toes.

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