What is Lupus?

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Lupus is a chronic autoimmune disease that affects five million people worldwide, the vast majority of whom are women. The immune system is designed to fight against external or foreign substances inside the body. In the case of lupus, the immune system attacks the patient’s body and can inadvertently damage healthy organs such as the heart, lungs, kidneys, skin and even the brain. Systemic lupus erythematosus (SLE) is the most common type of lupus that most people identify as "lupus." Other types of lupus are cutaneous erythematosus, drug induced or neonatal.

Lupus explained in first person

Professionals and patients explain how you live with the disease
The sun is the main source of ultraviolet light and is enemy no. 1 for patients with lupus, because it can trigger the disease or trigger flares at any time in its development.
Listen to your doctor, trust him, and it’s very important to stick to the treatment. And think, I have lupus, but lupus doesn't have me.

Lupus forms part of the so-called autoimmune diseases. The immunological system of the body normally produce proteins called antibodies in order to protect the body from viruses, bacteria, and other foreign substances called antigens.

In an autoimmune disease, like lupus, the immunological system mistakenly identifies the body's own cells as if they were foreign particles (antigens) and it goes into action to remove them, producing antibodies “against itself”. These antibodies are called autoantibodies and are bound with their own antigens to form immune complexes that are the cause of the inflammation and damage in the tissues.

Systemic lupus erythematosus (SLE), as it name indicates, is also a systemic disease. This means that it can affect many organs (skin, joints, kidneys, heart, lungs, etc.), but half of the patients with lupus are affected, almost exclusively, in the skin and joints.

Lupus is a chronic inflammatory disease, which means that the action of the immune system produces inflammation in the organs affected that persist for a long period of time and even for life. However, lupus is characterised by combining periods of major activity or flare-ups (exacerbation) with others of inactivity (remission).

With the appropriate follow-up and treatment, more than 90% of people with lupus have a normal life expectancy. It can present in different grades and intensities: there are mild cases, as well as moderate and severe that are more difficult to treat and control.

How common is Lupus?

Approximately 1 in every 1,000 inhabitants has lupus. There are more than 5 million people worldwide affected with lupus.

Lupus can affect both females and males of different races, ethnic groups, and ages. However, it affects much more females than males and, although it can present at any age, it is more common between 15 and 44 years.

Although the disease affects people of all races and ethnic groups, it is most commonly suffered by Latin American, Afro-American, and Asians of mixed race.

Types of Lupus

Man with skin blemishes

Systemic lupus erythematosus. It is the most common and can affect many parts of the body. It can be difficult to diagnose, as there are no two patients who present with exactly the same clinical signs, and their symptoms can be confused with other diseases or disorders.

Woman with spots on her face typical of Lupus or cutaneous erythematosus

Cutaneous lupus erythematosus. It usually only affects the skin and is characterised by a rash on the face, legs and/or arms.

Pill with prescription meds

Drug-induced lupus. Represents 10% of all cases of lupus and occurs as a reaction to certain types of drugs. Its symptoms are similar to those of the systemic form, but they are usually milder and remit when the medication is stopped.

Baby lying down with lupus infantileus

Neonatal lupus. An unusual type of lupus that affects the newborn. It may develop in children of mothers with lupus, since the antibodies of the mother are present in the neonate. The symptoms usually disappear at 6-8 months of age, coinciding with the complete elimination of the maternal antibodies.

Substantiated information by:

Claudia Castrillo
Gerard Espinosa Garriga
José-Manuel Mascaró Galy
Luis F Quintana Porras
Núria Baños López
Ricard Cervera Segura
Roser Ventura Roca

Published: 20 February 2018
Updated: 1 June 2023

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