generality
L'immunosuppressionthe immunodeficiency, is the medical condition in which an individual's immune system is functioning less effectively than normal or not functioning at all.
There are at least two ways to classify immunodeficiency and make it easier to consult the triggers. A first classification uses, as a criterion of distinction, the affected component of the immune system (immunosuppression based on the affected component). A second classification uses the congenital or acquired origin of the condition (immunosuppression based on origin) as a distinguishing criterion.
The following are essential to diagnose immunosuppression: physical examination, medical history, white blood cell count, T cell count, and immunoglobulin count.
Therapy depends on the triggering causes: some causes involve forms of immunodeficiency that are more treatable than others.
Brief review of the immune system
Il immune system it is the defensive barrier of an organism against threats coming from the external environment - such as for example viruses, bacteria, parasites, etc. - but also from the inside - such as for example cells that have gone mad (cancer cells) or malfunctioning.
To fulfill its protective functions, the immune system can rely on various organs, particular cells and glycoproteins; together, all these elements make up a sort of "army" appointed to take action and attack anything that constitutes a potential threat to the organism.
The constituent organs of the immune system include the spleen, the tonsils, bone marrow, thyme and lymph nodes; among the cells of the immune system, i White blood cells (granulocytes, monocytes and lymphocytes); finally, among the glycoproteins of the immune system, the antibodies.
What is Immunosuppression?
Definition of Immunodepression
L'immunosuppressionthe immunodeficiency, is the medical condition in which an individual's immune system is functioning less effectively than normal or not at all.
Hence, a subject with immunosuppression - also called immunosuppressed subject - is a person who has little or no immune defenses and is therefore more prone to infections, to get cancer, etc.
Types and Causes
What are the Causes of Immunosuppression?
There are at least two classifications of immunosuppression.
For one of these two classifications, the distinguishing criterion is the component of the immune system that fails to perform its functions (classification based on the affected component).
For the other of the two classifications, however, the criterion of distinction is the congenital or acquired origin of the condition (classification based on origin).
Regardless of the distinction criteria, classifying immunosuppression made it possible to simplify the consultation of the numerous triggering causes.
Classification of Immunosuppression based on the affected component
The classification based on the affected component of the immune system recognizes the existence of:
- An immunosuppression due to a deficiency / absence of the so-called humoral immunity.
Humoral immunity is that part of the immune response that belongs to B lymphocytes, plasma cells or antibodies. Hence, deficiency immunodeficiency / absence of humoral immunity is a deficiency / absence immunodeficiency of B lymphocytes, plasma cells or antibodies.
Main causes: multiple myeloma, chronic lymphoid leukemia and AIDS.
More dangerous infectious agents, for humans, in such circumstances: - Streptococcus pneumoniae
- Haemophilus influenzae
- Pneumocystis jirovecii
- Giardia intestinalis
- Cryptosporidium
- An immunosuppression resulting from a deficiency / absence of T lymphocytes.
T lymphocytes are a component of white blood cells.
Main causes: lymphoma, cancer chemotherapy, AIDS, bone marrow transplantation, organ transplants in general and glucocorticoid-based drug therapies.
More dangerous infectious agents, for humans, in such circumstances: - Herpes simplex virus
- Mycobacterium
- Listeria
- Intracellular pathogenic fungi
- An immunosuppression due to a deficiency / absence of the so-called neutrophil granulocytes (part of white blood cells). In the medical setting, the deficiency / absence of neutrophilic granulocytes is known as neutropenia.
Main causes: cancer chemotherapy, bone marrow transplant and chronic granulomatosis.
More dangerous infectious agents, for humans, in such circumstances: - Enterobacteriaceae (or Enterobacteriaceae)
- Streptococcus oralis
- Pseudomonas aeruginosa
- Enterococcus bacteria
- Mushrooms of the genus Candida
- Mushrooms of the genus Aspergillus
- An immunosuppression resulting from the absence of the spleen. In medicine, the absence of the spleen is a condition that is called asplenia.
Main causes: splenectomy, spleen trauma and sickle cell anemia.
More dangerous infectious agents, for humans, in such circumstances: - Bacteria equipped with a polysaccharide capsule (e.g. Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis)
- Protozoa of the genus Plasmodium
- Protozoa of the genus Babesia
- An immunosuppression resulting from a generalized functional deficiency of all components of the immune system.
Main causes: congenital dysfunctions of the immune system.
More dangerous infectious agents, for humans, in such circumstances: - Bacteria of the genus Neisseria
- Streptococcus pneumoniae
Classification of Immunosuppression by Origin
The classification of immunosuppression according to the origin recognizes the existence of two types of immunodeficiency: theprimary immunosuppression (o congenital immunosuppression) and thesecondary immunosuppression (o acquired immunosuppression).
All those conditions that determine a certain degree of immunodeficiency belong to the type "primary immunodepression" since birth (NB: the term "congenital", used as an alternative to "primary", means "present from birth"). Transmissible from parents to offspring (hereditary diseases), the conditions responsible for congenital immunosuppression are the result of chromosomal abnormalities, which may be located on autosomal chromosomes or on sex chromosomes.
According to the most recent studies, there are at least 80 conditions associated with congenital immunodeficiency; among these, they deserve a mention:
sex chromosome X-linked agammaglobulinemia, common variable immunodeficiency, severe combined immunodeficiency (SCID), DiGeorge syndrome, and congenital hypogammaglobulinemia.
Therefore, taking into consideration the "secondary immunosuppression" typology, this includes all those medical conditions that a human being can develop over the course of life and which affect the effectiveness of the immune system to a greater or lesser extent (NB: the term "acquired ", Used as an alternative to" secondary ", it means" developed in the course of life "). Conditions responsible for secondary immunodeficiency can result from:
- A severe state of malnutrition;
- A drug therapy based on chemotherapy, disease-modifying antirheumatics (DMARDs), immunosoppressori o glucocorticoids;
- Tumors, such as leukemias, lymphomas or multiple myeloma;
- Some infections of a chronic nature, such asAIDS or epatiti virali;
- Absence of the spleen (asplenia).
Risk Factors of Immunosuppression
All subjects with a family history of primary immunosuppression are at risk of immunodeficiency, as the conditions responsible for this type of immunosuppression are generally heritable.
They are also at risk of immunosuppression:
- Those who, for different reasons, have come into contact with the body fluids of an AIDS patient and have developed the same infectious pathology;
- Those who, due to a tumor, rupture of the spleen, an infection, etc., have had to undergo surgery splenectomia, for the removal of the spleen;
- The elderly, as aging causes the white blood cell-producing organs to be less effective;
- Those who, due to lack of availability or for other reasons, do not take an adequate amount of protein. Proteins are essential for a highly efficient immune system;
- Those who do not sleep an adequate number of hours during the night. During the night's sleep, the human body processes the proteins introduced in the diet and uses them to fight potential pathogens. Those who do not get enough sleep during the night cannot effectively use proteins for the aforementioned purpose, therefore they are more vulnerable to infections;
- Color that, due to a tumor, have to undergo chemotherapy.
Symptoms and Complications
What are the Symptoms of Immunosuppression?
When we talk about symptoms and signs of immunosuppression, we refer to the symptoms and signs of infectious diseases that can result from a lowering or, in more serious cases, from the absence of immune defenses.
Infectious diseases resulting from a state of immunosuppression can be bacterial, viral, fungal or parasitic in nature and can have the symptomatic characteristics of pneumonia, cold, flu, sinusitis, conjunctivitis, etc.
Diagnosis
What tests are needed for the Diagnosis of Immunosuppression?
Generally, the diagnostic process to which patients with a suspected form of immunosuppression are subjected includes:
- A thorough physical examination;
- A careful medical history;
- A test for quantifying white blood cell levels;
- A test for quantifying T-cell levels;
- A test for quantifying immunoglobulin (or antibody) levels.
If doubts remain after this series of diagnostic tests, doctors can rely on another very reliable test known as antibody test (in English it is antibody test).
The antibody test consists of giving the patient a vaccine and evaluating, after a few days or weeks, how the patient's immune system reacts to the vaccination. If the subject under examination does not suffer from immunosuppression, his immune system works adequately and produces, following the vaccine, the right quantities of antibodies; vice versa, if the examined subject suffers from immunosuppression, his immune system is malfunctioning or not functioning at all and, despite the stimulation of the vaccine, it does not produce any useful antibody.
Therapy
What are the Cures for Immunosuppression?
Treatment of immunosuppression depends primarily on what affected the functioning of the immune system, i.e. the triggering causes.
Some triggers are treatable and this allows healing to be achieved; other causes, on the other hand, are difficult to cure or not at all and this makes it essential to resort to therapies that remedy the deficiencies of the immune system and therapies against possible consequences (eg infections).
Regardless of the causes of immunosuppression, always valid advice for those with a pathological decline in immune defenses is minimize exposure to pathogens.
Primary (or Congenital) Immunosuppression
Congenital immunosuppression is the result of incurable chromosomal abnormalities. Therefore, a person suffering from a chromosomal defect, which causes immunosuppression from birth, is destined to live with an ineffective immune system and with the risk of easily developing infections.
In such circumstances, however, there are remedies, which aim to compensate for the deficiencies of the immune system; the aforementioned remedies include:
- La replacement therapy with immunoglobulins. This treatment involves the administration of antibodies intravenously or subcutaneously.
- Il hematopoietic stem cell transplantation. Hematopoietic stem cells are the cells that give rise to all blood cells.
- La administration of specific cytokines.
The purpose of these treatments is to prevent the onset of infections and other diseases related to a decline in the immune system.
Secondary or Acquired Immunosuppression
The treatment of secondary immunosuppression is a large and complex topic, as the possible triggering causes are numerous, sometimes treatable and sometimes not.
For some forms of acquired immunodeficiency (e.g. leukemia, multiple myeloma, etc.), the aforementioned hematopoietic stem cell transplant, the aforementioned replacement therapy with immunoglobulins or bone marrow transplantation are valid.
For secondary immunodeficiency due to AIDS, there are various therapies (for example antiretroviral therapy), but none are truly 100% effective in every individual.
For acquired immunosuppression resulting from conditions such as malnutrition or chemotherapy treatment, the only solution is simply to remedy the triggering factor (eg: in case of malnutrition, the remedy is to re-establish a correct diet).
Treatment of the possible consequences of Immunosuppression
An immunosuppressed person can very easily develop bacterial, viral, fungal and / or parasitic infections.
In the presence of infections, possible remedies consist of:
- Antiviral drugs and interferon, if the infection is due to viruses. Examples of antiviral drugs used are: amantadine, ramantadine and aciclovir.
- Antibiotics, if the infection is due to bacteria.
- Antifungal (or antifungal) drugs, if the infection is due to fungi.
Prognosis
If treated properly, many forms of primary immunosuppression have a favorable prognosis. In fact, despite the triggering causes are incurable conditions, early and regular treatment of the deficiencies of the immune system guarantees patients a normal life span.
Moving on to secondary immunosuppression, the prognosis for this problem depends a lot on the severity of the triggering causes. For example, an acquired immunodeficiency due to a leukemia has a much poorer prognosis than an acquired immunodeficiency due to a state of malnutrition, as leukemia is a more complex condition to treat.
Prevention
Is it possible to prevent immunosuppression?
Primary immunosuppression is not preventable in any way, as it depends on chromosomal abnormalities that appear during embryogenesis or uterine development, for unknown reasons. Secondary immunosuppression, on the other hand, is preventable only if the triggering causes are. Think, for example, of the acquired immunodeficiency due to AIDS: avoiding any contact with the body fluids of a person with AIDS, the same infection does not develop, therefore not even immunosuppression.
Immunosuppression and Vaccines
Generally speaking, a subject affected by immunosuppression cannot undergo the so-called live attenuated vaccines (eg: the MMR and MPRV vaccine), as in these there is an active component of the pathogen against which immunization is to be obtained; on the contrary, it can obtain all inactivated vaccines (eg the pertussis vaccine), since in these the microorganism for which immunization is to be obtained has been previously killed (and is therefore harmless).
