We are unaware of the number of dangers that surround us every day. Perhaps this is why the immune system does a job that is only appreciated the day it fails.
In this article we will review above the main types of autoimmune diseases and how they affect us. But first, let’s start with the simplest.
What is the immune system?
The immune system is a group of cells coordinated with each other which specialize in protecting the body against external agents that could lead to deterioration of health, such as infections or disease. Like everything, it’s not perfect, and some of these agents manage to pierce the defense and cause discomfort, infections, etc.
The problems are exacerbated when it is the immune system itself that is not optimal. There are different errors in this system, such as a lack of response (immunodeficiency), an exaggerated response (hypersensitivity) or an attack on the body itself (autoimmune diseases). In this article, I will focus on the latter group.
Autoimmune diseases have in common the loss of immune tolerance, i.e. detect antigens (Substances that are detected by the immune system and cause it to activate) possess the body. Tolerance is a number of mechanisms that exist to prevent this; for example, if a lymphocyte (immune system cell) is activated with its own antigen the moment it is generated in the producing organ (spleen and scam), the organ itself is responsible for the elimination of that cell so as not to damage the body.
The immune system uses antibodies, Molecules that bind to said antigens, to signal other immune cells to attack them. Loss of tolerance is detected by the presence in the body of autoantibodies (antibodies that signal normal body elements as antigens) and autoreactive T cells (lymphocytes that recognize their own antigens), which for some reason have not been eliminated.
Main types of autoimmune diseases
Up to 80 types of autoimmune diseases are known today, some with a higher prevalence than others. Many of them have similar symptoms (such as inflammation), which makes the task of diagnosis difficult. Usually, they are categorized into complex diseases because there are several factors that trigger the problem, such as hormonal, genetic or environmental components.
I will not devote myself to explaining all the existing autoimmune diseases, but I will talk about the most recognized to expose different cases.
1. Type 1 diabetes mellitus (DM1)
Diabetes is one of the metabolic alterations that most affects humans. In 2015, 400 million cases had been diagnosed worldwide. There are different types of diabetes mellitus, one of which is autoimmune. I’m talking about type 1 diabetes mellitus, which results in 5% of diagnosed cases.
The onset of DM1 usually occurs in adolescence, and what happens is the immune system removes islet cells from the pancreas, Which are responsible for making the hormone insulin, causing the onset of diabetes due to its lack.
2. Multiple sclerosis
It is a type of chronic autoimmune disease that demyelinates the central nervous system. In this case, the cells of the immune system, lymphocytes and macrophages, destroy the myelin which covers the nerve fibers, which plays an important role in maintaining nerve impulses. Without her, the neuron is unable to send correctly information.
It is one of the most common diseases affecting the nervous system in the world (2.5 million cases diagnosed worldwide), and its symptoms are signs of failure to transmit information, such as fatigue. , lack of balance, impaired vision and speech, and tremors.
3. Rheumatoid arthritis
This type of autoimmune disease affects the joints because the immune system gradually destroys them. It has a high prevalence (between 0.5 and 1% of the world population), with a higher frequency in women.
Rheumatoid arthritis causes pain, swelling and stiffness in the joints, Facts caused by the attack of immune cells on this tissue. The exact causes of the disease are unknown, although hormonal, environmental and genetic components have been discovered.
4. Systemic lupus erythematosus (SLE)
SLE, or simply lupus, is one of the most common autoimmune diseases. In Spain, it is estimated that 9 out of 10,000 people suffer from it. It is a systematic disease, in other words, the whole body is under attack by the immune system. Indeed, autoantibodies against nucleic antigens (ANA) are generated, that is to say they target elements of the cell nucleus, such as DNA or histones.
Lupus is a type of autoimmune disease that has very characteristic symptoms, such as a rash in the form of a butterfly on the face, photosensitivity, or kidney failure. the last this can lead to the death of the patient.
The reasons that trigger the disease are not known, although there is a strong genetic influence. In addition, it has also been considered to be more common in women, and more particularly in certain ethnic groups. African American and Hispanic women are at greater risk of contracting the disease than Caucasian women.