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8. The all-Russian system of simulation training, testing and certification
in health care / N.B. Naygovzina, V. B. Filatov, M. D. Gorshkov [etc.] // Virtual
technologies in medicine: scient. - pract. journ. - 2013 . - â 1 (9). - P. 8. jour.
- 2013. -â 1 (9). - P. 8.
Kudratova Zebo Erkinovna- Assistant of the Department of Clinical and
Laboratory Diagnostics; Muhamadieva Lola Atamuradovna - MD, Associate
Professor, Head of Department No. 3 of Pediatrics and Medical Genetics.
Samarkand State Medical Institute Samarkand, Uzbekistan
PATHOGENETIC FEATURES OF BRONCH-OBSTRUCTIVE SYNDROME IN
CHILDREN
Kudratova Z.E., Muhammadieva L.A.
Abstract: Bronchial obstructive syndrome (BOS) in children has been
attracting the attention of both researchers and medical practitioners for
many years, due to the widespread and heterogeneous nature of its
development, and therefore, difficulties in differential diagnosis. Of
particular difficulty is the differentiation of various manifestations of airway
obstruction in young children due to the high incidence of biofeedback as
the main syndrome, secondary syndrome, and even iatrogenic.
Keywords: bronchial obstructive syndrome, infectious pathology,
inflammation, hypersecretion;
Bronchial asthma (BA) and various acute bronchial obstructive
pathologies - obstructive bronchitis (OB), bronchiolitis, acute stenosing
laryngotracheitis (OSLT - false croup), whooping cough - diseases in which
violation of the airway, especially the bronchi, is the main manifestation. The
identification and treatment of biofeedback is a key point in the diagnostic
and therapeutic algorithms of these diseases [1,2]. The term "bronchial
obstruction" refers to a pathological condition resulting from impaired
patency of the bronchi with subsequent increase in resistance to air flow
during ventilation and characterized by episodes of shortness of breath as a
result of bronchoconstriction, inflammatory infiltration, hypersecretion and
dyskrinia of the submucous glands, edema and hyperplasia of the mucous
membrane of the respiratory tract, in particular [1, 3]. From a biological
point of view, bronchial obstruction has a protective and adaptive nature,
preventing the penetration of various foreign agents, including infectious
pathogens and allergens, into the alveoli, thus preventing the development
of pneumonia, and therefore is a universal mechanism for the protection of
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the respiratory tract through inflammation, hypersecretion of mucus ,
mucociliary transport, cough and even bronchospasm [3,4].
Pathogenesis. During the formation of biofeedback, inflammation of the
airways develops with the participation of epithelial and endothelial cells,
granulocytes, macrophages, monocytes, and there may be T-cell activation
in response to an infectious antigen or allergen [2]. As a result of
inflammation, a violation of the geometry of the small bronchi is formed due
to thickening of the wall, closure of the lumen by mucus and cellular detritus,
increased release of pro-inflammatory cytokines, increased bronchial
hypersensitivity, impaired neuroregulatory mechanisms in connection with
parasympathetic hyperreactivity [5,7]. Violation of mucociliary clearance
(the process of cleansing the respiratory tract) occurs both with excessive
sputum formation and with insufficient sputum, which leads to stagnation
of sputum, as a result of which the bronchial drainage function suffers and
the ventilation function of the lungs is impaired, the effectiveness of the
protective mechanisms, mucociliary transport and cough, are reduced
Colonization of the bronchi by pathogenic microflora is growing. Violation
of sputum transport leads to the maintenance and progression of
inflammation and bronchial obstruction [6,10].
Clinically, the degree of impaired bronchial patency with various
pathologies depends on the ratio of individual components of bronchial
obstruction, the presence of genetically determined bronchial
hyperreactivity, the characteristics of causative factors and inflammation.
The most important pathophysiological components of acute BOS in
children are edema of the bronchial mucosa, mucus hypersecretion and
bronchospasm [8,9].
With the protracted nature of BOS, hyperplasia of the mucous
membrane develops, and with chronic inflammation typical of bronchial
asthma and bronchopulmonary dysplasia (BPD), the phenomena of fibrosis
and sclerosis gradually form, which indicates structural restructuring of the
bronchi (remodulation) [7, 8]. Most often and clinically bright, BFB is
manifested in children of the first years of life, which is due to
morphofunctional features of the respiratory system: narrow airways,
insufficient elasticity of the lungs, soft cartilage of the bronchial tree,
insufficient stiffness of the chest, tendency to develop edema,
hypersecretion of viscous mucus, weak development of smooth muscles of
the bronchi [3, 6]. A special place in the formation of increased
bronchoreactivity and the development of biofeedback is occupied by
neuroreflective mechanisms, the basis of which is the functioning of the
autonomic nervous system. Autonomic effects in young children are
differently represented in different organs, tend to generalize, are very
labile, quickly transfer from one system to another [7]. In healthy infants,
Scientific research results in pandemic conditions (COVID-19)
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the tone of the parasympathetic section of the autonomic nervous system
(vagotonia) predominates, which causes narrowing of the bronchi,
vasodilation, sweating, peristalsis and an increase in the tone of the
digestive organs, which is manifested by pastiness, the development of
edema and hyperproduction of dense secretions, gastroesophageal disc
disease, and gastroesophageal disc disease development of biofeedback
Under conditions of vagotonia, the normal balance between
bronchoconstriction and bronchodilation with the involvement of various
receptors is disturbed. This dysfunction can lead to the development of
reflex bronchospasm and bronchial hyperreactivity, leading to the
formation of non-allergic AD mechanisms. β2-adrenergic receptors are
abundantly present in the airways and are present on smooth muscle cells,
epithelial cells, submucosal gland cells, numerous inflammatory cells, in
alveoli and presynaptic nerves [3,5,6]. The function of the β2-adrenergic
receptor depends on the connection with the Gs protein, stimulated by
adenylate cyclase, which increases the level of cyclic adenosine
monophosphate in the cell, the high content of which, in addition to relaxing
the smooth muscles of the bronchi, inhibits the release of mediators of an
immediate hypersensitivity reaction from inflammatory cells (primarily
from mast cells), which is important for children with atopy. After this, the
sensitivity of β-adrenergic receptors to further stimulation decreases.
Another group of receptors is muscarinic (cholinergic). Of their 5 types, M1,
M2, and M 3 receptors are present in the lungs. The tone of the muscles of
the bronchi is determined mainly by parasympathetic (cholinergic)
innervation (vagotonia) and is significantly enhanced in bronchial asthma.
The neurotransmitter acetylcholine, released in the nerve endings through
cholinergic receptors, leads to contraction of smooth muscles and enhances
the secretion of submucosal glands. Triggers for exacerbation of the process
(histamine, cold air, physical activity) initiate obstruction by a direct effect
on the receptors and activation of the cholinergic pathway, increasing
bronchial hyperreactivity. Smooth muscle cells are capable of producing
interleukins, growth factor, and pro-inflammatory cytokines that can
initiate, provoke, or support inflammation. In response to sensitization, γ-
interferon is released in smooth muscle cells, which is able to interact with
the M2 receptor, inhibiting its function, which subsequently leads to an
increase in the release of acetylcholine [3,4,5,6,7].
Thus, the anatomical and physiological characteristics of the respiratory
system and the vegetative orientation of young children determine the
significant frequency of biofeedback and the characteristic features of its
clinical manifestations. So, the leading one in the development of bronchial
obstruction in OB is pronounced edema of the bronchial mucosa and
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hypersecretion of viscous mucus, in contrast to bronchial asthma, in which
bronchospasm is the basis of bronchial obstruction [7].
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S. Atadjanova ,Candidate of Philosophy Sciences, Associate Professor,
National University of Uzbekistan, Uzbekistan
FROM THE HISTORY OF THE FORMATION OF THE INTERNATIONAL
CULTURAL COOPERATION OF THE PEOPLES OF CENTRAL ASIA (ON THE
EXAMPLE OF UZBEKISTAN WITH KAZAKHSTAN)
S. Atadjanova
