Журнал «Здоровье ребенка» 4 (55) 2014

The article described the impact on the formation of intracellular pathogens of inflammation in the airways in asthmatic children.

The infections play an important role in the pathogenesis of asthma and may be triggering in the development of the disease. Respiratory tract infections are impairing mucociliary clearance, violate neurogenic regulation of smooth muscles of the bronchi and cause damage to the epithelium and increase vascular permeability, increase production IgE. The bronchial hyperreactivity may be causes of the development and exacerbation of asthma.

The viruses are most commonly cause of the infections in infants. The viruses are infecting bronchial epithelium and contribute to increased production of interleukins. The increased level of IL-6 and IL-8 may be causes of a change in the regulation of T- and B-lymphocytes, neutrophils and promotes the accumulation of eosinophils, increases the formation of Ig E and histamine.

The characteristic features of modern infectious disease are increase of chronic infectious and inflammatory diseases. Usually, they are caused by persistent atypical microorganisms. The most common are Chlamydophyla pneumoniae, Mycoplasma pneumonia, herpes simplex virus type I-II, cytomegalovirus, Epstein-Barr virus.

The attention is paid to the factors which aggravating the risk of developing the disease, in particular, to the persistence herpes viruses, koronaroviruses, rhinoviruses, adenoviruses in the mucosa airway of patients with asthma. These pathogens damage the airway epithelium, depress the barrier properties of the bronchial wall and create conditions for the development of inflammation.

From 5 to 30 % of asthma associated with acute infection. There are Chlamydophila pneumoniae and Mycoplasma pneumoniae. These infectious pathogens are able to actively influence to the immune response, a secondary infection of the respiratory tract, an increase in bronchial hyperresponsiveness and development of bronchospasm. In addition, patients with atopic asthma are genetically predisposed to persistent course of intracellular infections.

Clinical diagnosis and differential diagnosis of Chlamydophila pneumoniae infection is significant difficulties in children. Most clinical variants of Chlamydophila pneumoniae infection begins gradually, with a predominance of non-specific symptoms, such as weakness, decreased of performance, dizziness, which can be for a long time. Most often infection may be asymptomatic. The final diagnosis based on the results of laboratory studies of Chlamydia in the epithelial cells and their antigens and antibodies specific class M, A, G to Chlamydophila pneumoniae.

Important pathogenetic components of herpetic disease is sensitization of organism by antigen of herpes simplex virus. Develop delayed-type hypersensitivity reaction with infiltration of cellular elements in rash that clinically recorded as redness, swelling, itching in the outbreak of herpetic lesions. Clinical features of herpes virus infection in patients with allergy is a more severe course of infection.

Changing the aspect ratio Th1- and Th2-cells is observed in a variety of infections caused by intracellular agents. Th1-type cells enhance cellular immune response and  express IL-2, IFN-γ. Th2-cells mediate the development of humoral immune response and produce IL-4, IL-5, IL-13.

When severity of infection is increase, may be change of the phenotype of T- helper cells from Th1 to Th2.

In case the children have comorbid disease - asthma and intracellular infections, the chronic inflammation is constantly maintained in the airway wall. Viruses can damage the airway epithelium, oppress the barrier properties of the bronchial wall than create conditions for the development of inflammation, promote overproduction of Ig E, sensitization to non-infectious agents.

Thus, the increase of the prevalence of asthma is not always sufficient efficacy of basic anti-inflammatory therapy, the high prevalence of respiratory Chlamydia infection, Mycoplasma infection, herpes infections require the development of additional measures to the control asthma, preventing or slowing airway remodeling processes and improving the quality of life of children with this chronic disease. The concept of "asthma, difficult to treat" is considered in various aspects. Develop specific treatments children with a combination of asthma and infection with intracellular agents such as Chlamydophila pneumoniae, Mycoplasma pneumonia, herpes simplex virus type I-II, cytomegalovirus, Epstein-Barr virus can help to achieve these goals.