Asthmatic bronchitis is a respiratory allergy that occurs with a predominant lesion of the bronchi of medium and large caliber. Manifestations are paroxysmal cough with difficult forced, noisy exhalation; shortness of breath of expiratory type. Diagnosis includes consultation of a pulmonologist and allergist, auscultation and percussion of the lungs, lung radiography, skin allergy tests, immunoglobulin and complement studies, bronchoscopy. Treatment consists in the appointment of bronchodilators, expectorants and antihistamines, antispasmodics, physiotherapy, exercise therapy, massage.
Asthmatic bronchitis is an infectious and allergic disease of the lower respiratory tract, characterized by mucosal hypersecretion, swelling of the walls, spasm of large and medium bronchi. In this disease, unlike bronchial asthma, there are usually no attacks of severe suffocation. Nevertheless, in modern pulmonology, disease is regarded as a condition of predastma. Most often, disease develops in children of preschool and early school age with a burdened history of allergic diseases.
Asthmatic bronchitis causes
Asthmatic bronchitis has a polyethological nature. At the same time, both non-infectious agents and infectious factors (viral, fungal, bacterial) entering the body aerobronchogenously or through the gastrointestinal tract can act as direct allergens. Among non-infectious allergens, household dust, fluff, plant pollen, animal hair, food components and preservatives are most often detected. Disease in children may be a consequence of drug and vaccine allergies. Polyvalent sensitization often takes place. Often in the anamnesis of patients there are indications of a hereditary predisposition to allergies (exudative diathesis, neurodermatitis, allergic rhinitis, etc.).
The infectious substrate of disease in most cases is pathogenic staphylococcus. This is indicated by the frequent seeding of the microorganism from the secretions of the trachea and bronchi, as well as an increased level of specific antibodies in the blood of patients with asthmatic bronchitis. Often asthmatic bronchitis develops after suffering from influenza, acute respiratory viral infections, pneumonia, whooping cough, measles. There have been repeated cases of asthmatic bronchitis in patients with gastroesophageal reflux disease. Depending on the leading allergic component, exacerbations of asthmatic bronchitis may occur in the spring-summer period (the flowering season of plants) or the cold season.
In the pathogenesis of asthmatic bronchitis, the leading mechanism is the increased reactivity of the bronchi to various allergens. The presence of neurogenic and immunological links of the pathological response is assumed. The site of the allergen-antibody conflict is the bronchi of medium and large caliber; small bronchi and bronchioles in asthmatic bronchitis remain intact, which explains the absence of pronounced bronchospasm and asthmatic attacks in the clinic of the disease. According to the type of immunopathological reactions, atopic and infectious-allergic forms of asthmatic bronchitis are distinguished. The atopic form is characterized by the development of type I allergic reaction (immediate type hypersensitivity, IgE-mediated allergic reaction); the infectious-allergic form is characterized by the development of type IV allergic reaction (delayed type hypersensitivity, cell-mediated reaction). There are mixed mechanisms of development of asthmatic bronchitis.
The pathomorphological substrate is a spasm of the smooth muscles of the bronchi, a violation of bronchial patency, inflammatory swelling of the mucosa, hyperfunction of the bronchial glands with the formation of secretions in the lumen of the bronchi. Bronchoscopy in the atopic form reveals a characteristic picture: pale but edematous bronchial mucosa, narrowing of segmental bronchi due to edema, a large amount of viscous mucous secretion in the bronchial lumen. In the presence of an infectious component, bronchial changes typical of viral-bacterial bronchitis are determined: hyperemia and swelling of the mucosa, the presence of mucopurulent secretions.
Asthmatic bronchitis symptoms
The course of asthmatic bronchitis is recurrent with periods of exacerbation and remission. In the acute phase, coughing attacks occur, which are often provoked by physical exertion, laughter, crying. Cough paroxysm may be preceded by precursors in the form of sharply occurring nasal congestion, serous-mucous rhinitis, sore throat, mild malaise. The body temperature during exacerbation may be subfebrile or normal. At first, the cough is usually dry, later during the day it can change from dry to wet. Acute cough attack is accompanied by difficulty breathing, expiratory shortness of breath, noisy, forced whistling exhalation. The asthmatic status does not develop at the same time. At the end of the paroxysm, sputum discharge is usually observed, followed by an improvement in the condition.
A feature of disease is the persistent repetition of symptoms. At the same time, in the case of the non-infectious nature of the disease, the so-called elimination effect is noted: coughing attacks stop outside the allergen (for example, when children live outside the house, changing the nature of nutrition, changing seasons, etc.). The duration of the acute period can range from several hours to 3-4 weeks. Frequent and persistent exacerbations of asthmatic bronchitis can lead to the development of bronchial asthma.
Most children suffering from disease have other allergic diseases – pollinosis, allergic diathesis on the skin, neurodermatitis. Multiple organ changes in disease do not develop, but neurological and vegetative changes can be detected – irritability, lethargy, increased sweating.
The diagnosis of asthmatic bronchitis requires taking into account the data of anamnesis, physical and instrumental examination, allergodiagnostics. Since asthmatic bronchitis is a manifestation of systemic allergosis, pulmonologists and allergologists-immunologists are engaged in its diagnosis and treatment. In patients with asthmatic bronchitis, the chest, as a rule, is not enlarged in volume. With percussion, the box tone of the sound above the lungs is determined. The auscultative picture of pathology is characterized by hard breathing, the presence of scattered dry whistling and various-sized wet wheezes (large and small bubbles).
Lung x-ray reveals the so-called “latent emphysema”: rarefaction of the pulmonary pattern in the lateral sections and thickening in the medial; strengthening of the lung root pattern. The endoscopic picture in asthmatic bronchitis depends on the presence of an infectious and inflammatory component and varies from an almost unchanged bronchial mucosa to signs of catarrhal, sometimes catarrhal-purulent endobronchitis.
In the blood of patients with this disease, eosinophilia, an increased content of immunoglobulins IgA and IgE, histamine, and a decrease in the complement titer are determined. To determine the cause of asthmatic bronchitis, it is possible to conduct scarification skin tests, elimination of the suspected allergen. To determine the infectious pathogen, sputum is sown on the microflora with the determination of sensitivity to antibiotics, and bronchial flushing waters are examined. In order to assess the degree of bronchial obstruction, as well as to monitor the course of the disease, a study of the function of external respiration is carried out: spirometry (including with samples), peak flowmetry, gas analysis of external respiration, plethysmography, pneumotachography.
Asthmatic bronchitis treatment
The approach to the treatment of asthmatic bronchitis should be comprehensive and individualized. It is effective to carry out long-term specific hyposensitization with an allergen in appropriate dilutions. Therapeutic microdoses of the allergen are increased with each injection until the maximum tolerated dose is reached, then they switch to treatment with maintenance dosages, which continue for at least 2 years. As a rule, children with asthmatic bronchitis who have received specific hyposensitization do not transform bronchitis into bronchial asthma.
When performing nonspecific desensitization, injections of histaglobulin are used. Patients with asthmatic bronchitis are indicated to take antihistamines (ketotifen, chloropyramine, diphenhydramine, clemastine, mebhydroline). If there are signs of bronchial infection, antibiotics are prescribed. The complex therapy of asthmatic bronchitis includes bronchodilators, antispasmodics, mucolytics, vitamins. To stop a cough attack, inhalers can be used – salbutamol, phenoterol hydrobromide, etc.
Nebulizer therapy, sodium chloride and alkaline inhalations are effective, improving the trophism of the mucosa, reducing the viscosity of mucus, restoring local ionic balance. Of the physiotherapeutic procedures for asthmatic bronchitis, medicinal electrophoresis, UFO, general massage, local chest massage, percussion massage are prescribed. It is advisable to conduct hydro procedures, therapeutic swimming, physical therapy, acupuncture, electroacupuncture. During periods of remission of asthmatic bronchitis, treatment at specialized resorts is recommended.
Prognosis and prevention
Usually, the prognosis for asthmatic bronchitis is favorable, but in 28-30% of patients, the disease transforms into bronchial asthma. To prevent the exacerbation of asthmatic bronchitis, allergen elimination, non-specific and specific hyposensitization, rehabilitation of chronic foci of infection are necessary. For the purpose of rehabilitation, hardening, therapeutic gymnastics, aeroprocedures, water procedures are shown. Patients are subject to dispensary observation by a pulmonologist and an allergist.