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Causes of adenoids in children
Last reviewed: 06.07.2025
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The causes of adenoids in children may be different, but for correct and effective treatment it is important to know not only the causes, but also the mechanisms of development of this pathology. The prevalence of this problem among children is very wide, so you need to know how to prevent the development of this pathology.
What are adenoids and how do they occur?
Adenoids is a somewhat non-specific term that cannot fully describe the problem. This name refers to the enlargement and hypertrophy of the pharyngeal tonsil of the nasopharynx. Since this tonsil is called adenoid in Latin, its enlargement is called adenoids or adenoid vegetations. The medical term that describes this problem is hypertrophy of the pharyngeal tonsil.
How does this hypertrophy occur? Tonsils are a cluster of several hundred lymphatic cells that immediately react to bacteria or viruses upon encountering them, triggering an immune response. Each person, including a child, has only six such tonsils, and the pharyngeal tonsil is one of them. The reasons for the enlargement of adenoids in children directly depend on the pathogenesis and function of the tonsils in the body.
The structure of the pharyngeal tonsil is identical to others. It consists of a capsule and reticular tissue. The reticular tissue has tree-shaped branches, between the processes of which there are lymphocytes. They have different degrees of maturity and, accordingly, take part in the immune response. Lymphocytes are the main immune cells that react when microbes enter the respiratory tract. The pharyngeal tonsil is located on the back wall of the pharynx at the top near the entrance to the back of the nasal cavity and hangs freely. When it is hypertrophied, it increases to different sizes, and thus it closes the entrance to the nasal cavity and disrupts the air flow in the nasopharynx.
When any cause acts on the tonsil, the same successive stages of its enlargement occur. A microbe, getting on the mucous membrane, immediately activates the release of these lymphocytes from the tonsils and, with a small number of these bacteria, when they have not yet had time to multiply, the lymphocyte absorbs it. This is how the local protective reaction of the mucous membrane is carried out. Under the influence of certain factors, the number of mature "working" lymphocytes from the tonsil may not cope with the number of microbes. This makes the active centers react and produce a little more "mature" lymphocytes. If this process occurs constantly and the tonsils work under such stress, then to ensure the function, it is necessary for the number of cells to increase. This makes the tonsil work at full capacity. Such a process must be accompanied by hypertrophy in order to meet the body's needs for local protection.
This is how adenoids enlarge.
The main causes of adenoid development
Taking into account the pathogenetic features of adenoid development, it follows that the main reason for the constant tension in the tonsil is the child's frequent illnesses. Frequent infections lead to a chronic inflammatory condition, which subsequently leads to hypertrophy of the lymphoid tissue of the adenoids due to the constant need for protection. Therefore, the reason for the appearance of adenoids in a child's nose in most cases is precisely such frequent infections.
Another reason for the development of adenoids can be considered a local allergic process in the form of chronic allergic rhinitis. This disease is characterized by an increase in the amount of IgE, which makes the body produce many eosinophils and mast cells in response to allergies. These eosinophils infiltrate the tonsil, as a place where immunocompetent cells mature. This entails an increase in adenoids.
A very common cause of adenoid enlargement is chronic adenoiditis. The causes of adenoid inflammation in children directly depend on frequent illnesses and the constant maintenance of a local inflammatory process. A constant source of infection located in the pharyngeal tonsil makes them work more efficiently and, accordingly, increase in size.
Very important factors in the development of adenoids are family history and similar pathology in the child's parents. If the child was born with an anomaly of the bone skull or an unclosed upper palate, this may cause the development of adenoids.
Congenital or acquired immunodeficiencies in a child lead to the fact that local defenses must be strained. Therefore, an increase in adenoids and other tonsils can develop due to such a pathology.
Pollution of the environment with heavy particles in highly urbanized areas leads to the fact that the filtration mechanism of the cilia of the respiratory tract epithelium is reduced. Therefore, the tonsils must partially take over the function of such a cleaning mechanism. Thus, excessive unsatisfactory environmental factors can cause the development of adenoids.
The causes of adenoid development in children are not limited to frequent respiratory infections. The hereditary factor, the influence of environmental factors, and the presence of chronic foci of infection in the child play a very important role in this. All this must be taken into account during treatment, because first of all, it is necessary to influence the factors of adenoid development, and only then treat with medication.