The last decade was marked by a revision of views on the pathogenesis of bronchial asthma (AD) in both adults and children. It is proved that the disease is based on the chronic inflammatory process of the respiratory tract, which causes their hyperreactivity, which is clinically manifested by bronchial obstructive syndrome and other respiratory symptoms.
The basis of inflammation in AD is the increased activity of eosinophils, mast cells, macrophages, T2 helper lymphocytes, epithelial cells, endothelial cells of the smooth muscles of the bronchi, followed by secretion and activation of cytokines and other mediators that contribute to the chronic inflammation.
As a result of the inflammatory process, 4 variants of bronchial obstruction are formed:
acute bronchospasm;
swelling of the mucous membrane of the bronchi;
hypersecretion of mucus and the resulting obstruction by sputum of the lumen of the bronchi;
remodeling of the wall of the bronchi (structural changes in the bronchi of various calibers).
Given the morphofunctional features of the respiratory system in young children (narrowness of the airways, insufficient lung elasticity, flexibility of the cartilage of the bronchi, insufficient stiffness of the chest, poor development of the smooth muscles of the bronchi, copious vascularization of the respiratory tract, hypersecretion of goblet cells of viscous mucus), leading components of broncho the first years of life are pronounced edema of the bronchial mucosa and hypersecretion of mucus. These anatomical and physiological characteristics must be taken into account in the treatment of AD in young children when drawing up an individual plan of therapeutic measures, since AD is very difficult, often with poor effectiveness of bronchodilator therapy during treatment of acute episodes of the disease.
Based on the inflammatory concept of the development of the disease, the key provisions for the treatment of AD in young children are: The
treatment is prescribed taking into account the severity and period of the disease in a particular patient, the availability of anti-asthma drugs and the individual, social, family and economic characteristics of the family of a sick child.
AD therapy consists of a set of measures during exacerbation and in remission.
The most effective drugs for asthma control are inhaled glucocorticosteroids (IHC). Long-term therapy with IHC dramatically reduces the frequency and severity of exacerbations.
The most effective symptomatic drugs in the treatment of exacerbations of asthma are fast-acting inhaled b2-agonists, which are also the most effective among existing bronchodilators.
After achieving remission while maintaining control over the course of AD for at least 3 months, the dose of maintenance therapy can be gradually reduced to the minimum necessary.
Many drugs (GCS, b2-agonists, methylxanthines) in young children are metabolized faster than in older children and adults, and therefore, when administered orally, the drug should be used in higher doses than in older children.
Long-term therapy with IHC does not lead to an increase in osteoporosis and bone fractures, does not affect the growth of the child. The course of AD can be considered controlled if: the
signs of the disease, including nocturnal symptoms, are minimally expressed (ideally, they are absent);
exacerbations of the disease are episodic;
there is no need for the use of emergency drugs (b2-agonist) or the need for them is very low;
there is no need to limit the activity of the child, especially physical;
side effects from the use of prolonged pharmacotherapy are mild or absent.
Medicines for the treatment of AD in children are divided into two main groups:
Means for monitoring the course of the disease, aimed at the constant suppression of chronic allergic inflammation in the respiratory tract (anti-inflammatory basic pharmacotherapy), which are taken daily and for a long time.
Emergency care products that act quickly, stopping bronchoconstriction and the accompanying signs of exacerbation (wheezing with difficulty breathing out, heard at a distance, coughing) and which are used only to treat exacerbations of asthma.
The preferred route of administration of drugs is inhalation, because it allows you to create high and effective concentrations of medications directly in the respiratory tract and to minimize the development of systemic side effects. The introduction of drugs is carried out using various means of inhalation technology (delivery devices). Since small children (including infants) cannot actively coordinate respiratory movements, it is better to use a metered-dose aerosol inhaler (DAI) in combination with a delay chamber (baby-chaler, spacer, synchronizer, auto-chaler) to carry out control (anti-inflammatory) therapy. For emergency care and intensive care using bronchodilators, DAIs are used in combination with a spacer and a face mask or inhalations are carried out through a nebulizer. For lack of factory-made devices, an alternative could be a home-made device from a plastic bottle, from which the bottom is cut off, and the neck is modeled using hot water to fit the size of the mouthpiece of a metered-dose inhaler.
Anti-inflammatory therapy is prescribed in a continuous course with a total duration of at least 6 months (of which 3 months – at the optimal dose and 3 months – a gradual decrease to the minimum dose that supports asthma control). This is the minimum period required to suppress allergic inflammation in the airways. As the basic therapy, various IHCS (beclomethasone dipropionate, fluticasone propionate, budesonide), inhaled non-steroidal anti-inflammatory drugs (cromone, nedocromil sodium) and antileukotrienes (montelukast, zafirlukast) are used as basic therapy. When prescribing anti-inflammatory therapy, a stepwise approach is used (Table 1), which provides for a different volume and intensity of drug treatment, depending on the severity of the course (severity of symptoms) [5].
The principle of a stepwise approach to anti-inflammatory therapy involves 2 methods of prescribing drugs – “step up” and “step down”. In young children, in the first episodes of the disease, when the further nature of the course of AD is still unknown, the “step up” method is more often used. In this case, a treatment option is prescribed that corresponds to the severity of the disease immediately before treatment. In the absence of the effect of the treatment carried out for 2-3 weeks or aggravation of the further course of the disease, it is necessary to increase the dose of the anti-inflammatory drug or change it to a more powerful one (Cromona – on the IHC). The “step down” technique immediately prescribes the use of more intensive medications to achieve a quick effect with a gradual dose reduction and during a period of stable remission by changing the drug to a more gentle one (IHC – to crones). This approach is more appropriate in case of severe AD debut in young patients, especially in children with family history of hepatia significantly weakened by atopy, in which the prognosis of the further course of the process is more serious. Due to the fact that at this age AD is severe in most patients [2, 4], the “step down” method is preferable at the initial stage of treatment.
According to modern recommendations [1,2], the most effective basic drugs in young children are IHC, the therapy of which should be carried out from the first days of the acute period of the disease with moderate to severe illness. This prevents the possibility of subsequent relapse of asthma. Initial doses of IGCS for patients in the first years of life [6] are given in table 2, and equipotent daily dosages are given in table 3.
The purpose of IGCs can significantly reduce the use of systemic parenteral and, especially, oral GCS. Short-course trial therapy for IHC should be used more widely in the treatment of recurrent bronchial obstructive syndrome in children of the first years of life with early manifestations of allergies, since the influence of IHC on chronic inflammation prevents the formation of persistent AD and patient disability. The use of low and medium therapeutic doses of ICS allows you to effectively and safely control the disease in the vast majority of children with severe course. When prescribing high doses of IHC, the correlation between the benefits and the potential dangers of treating them should be taken into account. The most significant, but rare (less than 1%) possible side effect of long-term therapy of IHC is candidiasis of the oral mucosa. For its prevention, it is recommended that the child drink a little water 15-20 minutes after inhalation.
In order to reduce the dose of IGCS in severe cases, you can combine them with prolonged b2-agonists (25 μg of salmeterol in 1 breath). The latter have a bronchodilating effect for 12 hours,
and some anti-inflammatory effect. They can be prescribed simultaneously with non-hormonal drugs to enhance therapy with inhaled anti-inflammatory drugs (INPV) before deciding on the appointment of IHC. NSAIDs are used in children with mild asthma and in some patients with a moderate version of the disease, in whom asthma occurs in the form of periodic exacerbations, and persistent symptoms are mild. NSAIDs should be used in adequate doses throughout the treatment period. In patients with moderate severity during the period of seasonal exacerbations, a good prophylactic effect is achieved by the additional administration of a short course (4-6 weeks) of IHC in low doses against the background of long-term therapy with INVP, which provides satisfactory control over the course of AD in most children. The correct distribution of anti-inflammatory therapy allows for a planned break in treatment at the most favorable period for the patient.
Antileukotriene drugs (most often montelukast, which is prescribed for children from two years of age) are indicated for patients with physical and psycho-emotional stress and especially for children who have problems using the inhalation technique, because, unlike inhalation agents, they are used in oral form. If necessary, they can be combined with INVP and IHC to reduce their total dose.
Methylxanthines in young children should be used in the treatment of exacerbations as a “despair” therapy if the undertaken treatment using fast-acting b2-agonists, anticholinergics, parenteral and inhaled corticosteroids. For long-term basic therapy in young children, they should not be used due to the great risk of developing serious adverse reactions.
The use of inhaled cholinolytics in the treatment of acute episodes of AD in children of the first years of life is pathogenetically justified and highly effective, which is explained by the predominance of vagotonia in them. They are good to apply at the beginning of an exacerbation of the disease, but not for long, and in combination with mucolytics administered with a severe intravenous attack. This is due to the drying effect of atropine derivatives. A more pronounced bronchodilator effect is observed with a combination of oxytropium bromide and fast-acting b2-agonists, since they potentiate each other’s activity. If they are ineffective, it is possible to use b2-agonists of fast action orally and parenterally. In the formation of AD in young children, an important role is played by the causative agents of respiratory infections – viruses and bacteria, including atypical ones [7]. In this regard, during exacerbations of asthma, it is often necessary to decide on the appointment of antibiotics, and during remission, immunostimulants of microbial origin.
Indications for prescribing antibiotics for asthma are:
protracted asthmatic attack;
asthmatic status;
infection of the patient with pathogenic and atypical microbes (hemophilic bacillus, mycoplasmas, chlamydia, Staphylococcus aureus,
pneumonia streptococcus, etc.);
chronic foci of infection;
secondary catarrhal-purulent and purulent endobronchitis.
The choice of antibacterial drug is quite limited: cephalosporins, fluoroquinolones, macrolides. The advantage should be given to the latest generation of macrolides (azithromycin, clarithromycin, spiramycin), which are highly effective against these bacterial pathogens, create a high concentration in the focus of inflammation when administered orally, practically do not have side effects, are convenient to use, are well perceived by young children.
Indications for the appointment of bacterial immunostimulants:
burdened infectious history in a child;
concomitant foci of infection;
ARI as a trigger (provocateur) BA;
infectious syndrome with exacerbation of AD;
laboratory-confirmed decrease in indicators of the immune status (cellular and humoral links of immunity, local defense factors and phagocytosis);
detection of pathogens (in swabs of mucus from the nose, throat, in sputum).
Treatment of AD in young children should not be aggressive. It should strive to achieve control over the course of the disease with the most effective and safer basic means, avoid the simultaneous administration of a large number of drugs. The ideal option is monotherapy. Thanks to early diagnosis and the timely initiation of basic therapy for AD, especially in young children, the so-called hormone dependence has been almost completely eliminated in Ukraine over the past decade: the number of children requiring prolonged use of systemic corticosteroids has been dramatically reduced. Weighted tactics of basic treatment of AD can significantly improve the quality of life, physical development of patients, and eliminate the serious side effects of systemic hormone therapy.
