Diagnosis is based on data from an allergological history, clinic, specific diagnostics, radiological, immunological, and bnochem. and special bronchological and functional studies.
The most characteristic radiological changes in bronchial asthma are emphysema, stiffness of the roots, increased pulmonary pattern, mooring, fusion in the sinuses, and other changes in the pleura. Normal pulmonary pattern is rare. In the presence of an active inflammatory process in the lungs, peribronchial type infiltration predominates; focal and mixed types of infiltration are observed in 89% of patients.
Syndrome of bronchial obstruction during an attack is accompanied by characteristic changes in pulmonary volumes: an increase in OOL and its share in the OEL, as well as a sharp increase in bronchial resistance on exhalation, a decrease in FVC of the MVL and Tiffno index. These disorders are caused by bronchial obstruction (the main cause) and a deterioration in the elastic properties of the lung. Due to the unevenness of alveolar ventilation and violations of the ratio of ventilation and blood flow, ventilation and alveolar respiratory failure develop. The severity of respiratory failure in the interictal period depends on the severity of the disease; in accordance with this, obstructive changes of varying degrees are observed. The chronic course of bronchial asthma is characterized by a complex set of ventilation defects associated with obstruction of the bronchi. An objective measurement of the partial pressures of oxygen and carbon dioxide allows you to judge blood gases and ventilation status. In the acute stage of uncomplicated bronchial asthma, the severity of obstruction is associated with hypoxemia, respiratory alkalosis, a decrease in partial pressure and oxygen transport, and in some patients, respiratory acidosis. These disorders are especially pronounced with asthmatic status. Changes in peripheral blood are not characteristic. During seizures, the number of red blood cells and hemoglobin increases; white blood cell count depends on the activity of inflammation; eosinophilia is noted (bone marrow eosinophilia is more pronounced and constant), lymphocytosis. Leukocytosis and eosinophilia are evaluated with caution after administration of adrenaline and glucocorticosteroid drugs. Very high eosinophilia requires differential diagnosis with allergic bronchopulmonary aspergillosis, parasitic infections, Leffler’s syndrome. ESR and biochem. indicators of inflammation activity depend on the phase of the inflammatory process. Diagnostic value are proteinogram, C-reactive protein, serum glycoproteins, a2-globulinemia, hypergammaglobulinemia.
Eosinophilia is detected in sputum, there may be Kurshman spirals, Charcot-Leiden crystals (may be absent in freshly isolated sputum and appear when it is defended); increased activity of acid phosphatase (ten times higher than in serum), which indicates deep damage to the lysosomal membranes of neutrophils and macrophages. Histological examination reveals non-mucoid and degenerated cell elements, as well as eosinophilic detritus. In bronchial contents (bronchoalveolar lavage) with atopic asthma there is a decrease in the number of macrophages in two – two and a half times, an increase in the number of eosinophils in 5-10, neutrophils – in two to three times. In infectious bronchial asthma, macrophages prevail, there are few eosinophils, there are neutrophils. Bronchoscopy reveals diffuse catarrhal inflammation (in 50% of patients), diffuse catarrhal endobronchitis of the II degree (about 20% of patients), atrophic bronchitis (about a third of patients). Biochem. violations are different. They to a certain extent depend on the form, stage and severity of bronchial asthma and are characterized by changes in the blood levels of adaptive hormones, allergy mediators, proteolytic enzymes and other factors. Changes in cellular and humoral immunity are heterogeneous. In some patients, secondary immunological deficiency is noted; some have a relationship between the degree of immunity disorders and the severity of the disease and there is an improvement as a result of immunocorrective therapy.