The American Journal of Medical Sciences and Pharmaceutical Research
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TYPE
Original Research
PAGE NO.
42-46
10.37547/tajmspr/Volume07Issue05-09
OPEN ACCESS
SUBMITED
28 March 2025
ACCEPTED
24 April 2025
PUBLISHED
26 May 2025
VOLUME
Vol.07 Issue05 2025
CITATION
Tashmatova Gulnoza A’loyevna, & Khalilova Zilola Abdurauf qizi. (2025).
Gut Microbiome in Children with Bronchial Asthma Against the
Background of Mycoplasma and Chlamydial Infection: Features and Clinical
Significance. The American Journal of Medical Sciences and Pharmaceutical
Research, 7(05), 42
–
46.
https://doi.org/10.37547/tajmspr/Volume07Issue05-09
COPYRIGHT
© 2025 Original content from this work may be used under the terms
of the creative commons attributes 4.0 License.
Gut Microbiome in
Children with Bronchial
Asthma Against the
Background of
Mycoplasma and
Chlamydial Infection:
Features and Clinical
Significance
Tashmatova Gulnoza A’loyevna
Associate Professor, Department of chil
dren’s diseases of Tashkent
medical academy, Tashkent, Uzbekistan
Khalilova Zilola Abdurauf qizi
Doctoral candidate of the Department of Children's Diseases, Tashkent
Medical Academy, Tashkent, Uzbekistan
Abstract:
Asthma is the most common chronic
inflammatory disease of the airways, characterized by
episodes of obstruction. The aim of the study is to assess
the state of the gut microbiome in children with
bronchial asthma and to investigate its interaction with
Chlamydia pneumoniae and Mycoplasma pneumoniae
infections in the course of the disease. Materials and
methods. All patients were examined at the
Department of Pediatric Allergology of the Tashkent
Medical Academy. The study included 14 children with
severe, 23 with moderate, and 31 with mild forms of BA.
Age distribution: 7
–
10 years
–
23 children (34%), 11
–
14
years
–
20 children (30%), 15
–
17 years
–
25 children
(36%). Duration of the disease: 1
–
3 years
—
34 children
(50%), 3
–
6 years
—
34 children (50%). Gender
distribution: 43 boys (63%) and 25 girls (36%). Results.
All children with BA experienced breathing difficulties,
mainly at night. In 82.3% of cases, bronchial asthma
attacks (shortness of breath, dry cough) occurred 1
–
3
times per month, lasting 5
–
10 minutes. In patients
infected with M. pneumoniae and C. pneumoniae,
significant alterations in the gut microbiota were
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observed. These changes manifested as a decrease in
beneficial
bacteria
—
Bifidobacterium
and
Lactobacillus. In infected children, the number of
Bifidobacterium decreased by an average of 48%
(p<0.05), while Lactobacillus decreased by 42%
(p<0.01). Additionally, an increase in conditionally
pathogenic bacteria
—
Escherichia coli, Clostridium,
and Bacteroides
—
was detected: Clostridium
increased by 35% (p<0.01), Bacteroides by 29%
(p<0.05), and E. coli by 33% (p<0.01). These infectious
agents contribute to the development of dysbiosis,
characterized
by
a
reduction
in
beneficial
microorganisms (Bifidobacterium, Lactobacillus) and
an increase in conditionally pathogenic bacteria
(Escherichia coli, Clostridium, Bacteroides). Such
changes are associated with an enhanced systemic
inflammatory response and a higher susceptibility to
allergic reactions, which aggravate the clinical course
of the disease. Conclusion: Mycoplasma pneumoniae
and Chlamydia pneumoniae significantly affect the
composition of the gut microbiome in children with
bronchial asthma. These infectious agents contribute
to the development of dysbiosis, characterized by a
decrease in beneficial microorganisms (such as
Bifidobacterium and Lactobacillus) and an increase in
conditionally pathogenic microorganisms (such as
Escherichia coli, Clostridium, and Bacteroides). These
alterations in the intestinal microbiota are associated
with enhanced systemic inflammatory processes and
increased susceptibility to allergic reactions, which in
turn aggravate the clinical course of the disease.
Keywords:
Bronchial asthma, children, atypical
microflora, gut microbiota.
Introduction:
In recent years, growing attention has
been paid to the role of the gut microbiome in the
development and progression of chronic inflammatory
diseases, including bronchial asthma (BA). Bronchial
asthma remains one of the most prevalent chronic
diseases in childhood, with a multifactorial etiology
that includes genetic predisposition, environmental
influences, and infectious agents. Despite significant
advances in the understanding of asthma pathogenesis
and the development of modern treatment strategies,
many aspects remain poorly understood, especially in
cases where asthma is associated with atypical
pathogens such as Mycoplasma pneumoniae and
Chlamydia pneumonia [1, 3].
Recent scientific evidence has demonstrated a close
relationship between the state of the intestinal
microbiome and immune regulation. The gut
microbiota plays a critical role in shaping the immune
system, modulating inflammation, and maintaining
mucosal barrier function. Disruption of the microbiota
balance
—
dysbiosis
—
has been linked not only to
gastrointestinal diseases but also to systemic immune-
mediated disorders, including allergic diseases such as
asthma. In pediatric patients, the microbiota is more
dynamic and sensitive to external influences, making
early childhood a critical period for the formation of
immune tolerance and stable respiratory health [5, 8, 9].
Of particular interest is the interaction between gut
microbiota alterations and respiratory tract infections.
Mycoplasma and Chlamydia species are known for their
ability to cause persistent infections with a pro-
inflammatory effect. In children with asthma, chronic or
recurrent infections with these pathogens can lead to
prolonged inflammation and remodeling of the airways.
Moreover, these infections may influence the
composition and function of the gut microbiome
through systemic immune responses and antibiotic use,
further exacerbating immune dysregulation [2, 4, 10].
Understanding the characteristics of the gut
microbiome in children with bronchial asthma
associated with Mycoplasma and Chlamydia infections
could open new prospects for individualized treatment
approaches. This includes the use of probiotics,
prebiotics, and microbiota-targeted therapies, which
may help to restore microbial balance, improve the
course of asthma, and reduce the frequency of
exacerbations.
Additionally,
microbiome-based
biomarkers could assist in predicting disease severity
and response to therapy [6, 7].
Given the increasing prevalence of antibiotic-resistant
strains of atypical bacteria and the limitations of
standard asthma treatment in cases with infectious
components, the exploration of the gut-lung axis is both
timely and clinically significant. It contributes not only to
a deeper understanding of the pathophysiological
mechanisms involved but also to the development of
novel preventive and therapeutic strategies [1, 3, 5].
Therefore, the study of the gut microbiome in children
with bronchial asthma, particularly in the context of
Mycoplasma and Chlamydia infections, is of high
relevance. It represents an important direction in
pediatric pulmonology, immunology, and microbiome
research and holds promise for improving the quality of
life and clinical outcomes in affected children [9].
In this regard, it is relevant to study the role and
influence of C. pneumoniae, M. pneumoniae infections
on the course of BA in children. This promising area of
research is a real way to further improve specialized
medical care for children.
Purpose of the research
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The aim of study the characteristics of the intestinal
microbiome in children with bronchial asthma caused
by mycoplasma and chlamydial infections and to
determine its clinical significance.
METHODS
Between 2023 and 2025, a total of 68 children aged 7
to 17 years diagnosed with bronchial asthma were
observed. All participants were stratified by gender,
age, and severity of asthma. The study was conducted
at the Pediatric Allergology Department of the
Tashkent Medical Academy.
Among the 68 patients, 14 had a severe form of
asthma, 23 had a moderate form, and 31 had a mild
form. The age distribution was as follows: 7
–
10 years
–
23 children (34%), 11
–
14 years
–
20 children (30%), and
15
–
17 years
–
25 children (36%). Regarding disease
duration, 34 children (50%) had asthma for 1
–
3 years,
and 34 children (50%) for 3
–
6 years. The cohort
included 43 boys (63%) and 25 girls (37%).
A control group of 42 healthy children aged 7 to 17
years, recruited from schools in Tashkent, was also
examined for comparison. All participants underwent
serological testing for markers of Chlamydophila
pneumoniae,
Mycoplasma
pneumoniae,
and
Mycoplasma hominis.
Microbiological analysis of the intestinal microbiota
was performed in all subjects. This included culturing
samples on selective media to assess the balance
between beneficial and opportunistic microorganisms.
A quantitative and qualitative evaluation of key
bacterial groups was carried out, including
Bifidobacterium, Lactobacillus, Escherichia coli,
Clostridium, Bacteroides, and other representative
members of the gut microbiome.
RESULTS AND DISCUSSION
All children with bronchial asthma had difficulty
breathing mainly at night. In addition, 82.3% of
children often had attack equivalents (a feeling of
shortness of breath, dry paroxysmal cough), which
recurred 1-3 times a month, lasting from 5-10 minutes,
difficulty breathing was relieved on its own or after a
single use of bronchodilators.
A feature of the course of asthma in children living in
industrial regions was that a change of environment
contributed to a more rapid relief of the symptoms of
the disease.
During exacerbation of the disease in children with
intermittent bronchial asthma, the condition of
patients remained generally satisfactory. They
complained of difficulty breathing, shortness of breath
and dry cough.
In children with bronchial asthma infected with
Mycoplasma pneumoniae (M. pneumoniae) and
Chlamydia pneumoniae (C. pneumoniae), significant
changes in the composition of the intestinal microbiome
were detected, which confirms the influence of these
infections on the pathogenesis of the disease and the
development of dysbiosis.
In children with mycoplasma and chlamydial infections,
especially in severe cases of bronchial asthma, there is a
decrease in the number of beneficial bacteria, such as
Bifidobacterium and Lactobacillus. These bacteria play a
key role in maintaining normal intestinal function,
supporting local immunity and protecting against
pathogens. In children with M. pneumoniae and C.
pneumoniae
infections,
Bifidobacterium
counts
decreased by an average of 48% (p<0.05) and
Lactobacillus levels decreased by 42% (p<0.01)
compared with the control group.
Children with Mycoplasma and Chlamydial infections
showed an increase in the number of opportunistic
microorganisms, such as Escherichia coli, Clostridium
and Bacteroides. The number of Clostridium increased
by an average of 35% (p<0.01), and Bacteroides by 29%
(p<0.05), compared with children in the control group.
In the group with M. pneumoniae infection, the level of
Escherichia coli was increased by 33% (p<0.01), which
also indicates an imbalance in the intestinal microflora.
The imbalance of microflora caused by M. pneumoniae
and C. pneumoniae weakens the intestinal barrier
function. This contributes to increased permeability of
the intestinal wall and activation of systemic
inflammation, which can lead to the development of
allergic reactions and worsening of asthma symptoms.
In children with M. pneumoniae and C. pneumoniae
infection, increased levels of proinflammatory cytokines
(IL-6, TNF-
α) were recorded in the intestine, which also
indicates activation of inflammatory processes. In
children with severe bronchial asthma, the level of these
cytokines increased by 41% (p<0.05) compared to the
control group.
Changes in the gut microbiota were closely related to
disease severity. In children with mild asthma and M.
pneumoniae or C. pneumoniae infections, changes in
the gut microbiome were less pronounced. In this
group, a 15-25% decrease in beneficial bacteria was
observed, while in children with severe asthma, the
number of Bifidobacterium and Lactobacillus was
reduced by 45-55%, and the levels of opportunistic
bacteria such as Clostridium and Escherichia coli
increased by 30-40% (p < 0.01). This confirms that the
microbiome plays a key role in exacerbating
inflammation and disease symptoms.
Microbiome disturbances in children with M.
pneumoniae and C. pneumoniae also affect the immune
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response, increasing the risks of allergic reactions and
asthma exacerbations. This is because the gut
microbiome plays an important role in modulating
immune activity, including IgE levels and T-cell activity.
Children with infection have a 28% increase in IgE
levels (p<0.05) and an increased proinflammatory
response, which may maintain chronic airway
inflammation and contribute to the progression of
asthmatic symptoms.
Intestinal microbiota disturbances in children with
bronchial asthma who have had Mycoplasma
pneumoniae and Chlamydia pneumoniae infections
are accompanied by significant changes in the
composition of microflora, including a decrease in the
level
of
beneficial
bacteria
(Bifidobacterium,
Lactobacillus) and an increase in opportunistic
microorganisms
(Escherichia
coli,
Clostridium,
Bacteroides). Changes in the intestinal microbiome
correlate with the severity of the disease: the more
severe the form of bronchial asthma, the more
pronounced the disturbances in the microbiota. In
children with severe asthma, the number of beneficial
bacteria was reduced by 45-55%, while opportunistic
bacteria increased by 30-40%.
An imbalance in the intestinal microflora affects the
immune response, increasing IgE levels and promoting
the activation of proinflammatory cytokines. This can
increase inflammatory reactions in the airways and
exacerbate asthma symptoms.
The correlation between the state of the microbiota
and clinical manifestations of the disease indicates the
importance of the microbiome as one of the factors
influencing the development and course of bronchial
asthma in children who have had mycoplasma and
chlamydial infections.
It is important to consider changes in the intestinal
microbiota when developing new therapeutic
strategies for the treatment of bronchial asthma,
including the possible use of drugs that help normalize
the intestinal microflora and correct dysbiosis as part
of complex therapy.
CONCLUSION
Mycoplasma pneumoniae and Chlamydia pneumoniae
significantly affect the composition of the intestinal
microbiome in children with bronchial asthma.
Imbalance of microflora, decreased levels of beneficial
bacteria (Bifidobacterium, Lactobacillus) and an
increase in opportunistic microorganisms (Escherichia
coli, Clostridium, Bacteroides) contribute to increased
inflammation and allergic reactions. These changes,
especially in severe forms of the disease, confirm the
importance of treating dysbiosis and correcting
microbiota in the complex therapy of bronchial asthma
in children who have had M. pneumoniae and C.
pneumoniae infections.
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