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Chronic nonobstructive bronchitis - Diagnosis
Medical expert of the article
Last reviewed: 04.07.2025
Laboratory and instrumental diagnostics
Blood test
Catarrhal endobronchitis is usually not accompanied by diagnostically significant changes in the clinical blood test. Moderate neutrophilic leukocytosis with a shift in the leukocyte formula to the left and a slight increase in ESR, as a rule, indicate an exacerbation of purulent endobronchitis.
Determination of the serum levels of acute phase proteins (alpha1-antitrypsin, alpha1-glycoprotein, a2-macroglobulin, haptoglobulin, ceruloplasmin, seromucoid, C-reactive protein), as well as total protein and protein fractions, is of diagnostic value. An increase in the levels of acute phase proteins, a-2- and beta-globulins indicates the activity of the inflammatory process in the bronchi.
Sputum analysis
With low inflammation activity, exfoliated bronchial epithelial cells predominate in mucous sputum (about 40-50%). The number of neutrophils and alveolar macrophages is relatively small (from 25% to 30%).
With moderate inflammation activity, in addition to bronchial epithelial cells, the bronchial contents contain a large number of neutrophils (up to 75%) and alveolar macrophages. Sputum is usually mucopurulent.
Finally, severe inflammation is characterized by the presence of a large number of neutrophils (about 85-95%), isolated alveolar macrophages and dystrophically altered cells of the bronchial epithelium in the bronchial contents. The sputum becomes purulent.
X-ray examination
The importance of X-ray examination of patients with chronic non-obstructive bronchitis mainly lies in the possibility of excluding the presence of other diseases with similar clinical manifestations (pneumonia, lung cancer, tuberculosis, etc.). Any specific changes characteristic of chronic non-obstructive bronchitis cannot be detected on X-ray images. The pulmonary pattern is usually slightly changed, the pulmonary fields are transparent, without focal shadows.
Function of external respiration
The function of external respiration in patients with chronic non-obstructive bronchitis in most cases remains normal both in the remission phase and in the exacerbation phase. An exception is a small category of patients with chronic non-obstructive bronchitis, in whom during a pronounced exacerbation of the disease a slight decrease in FEV1 and other indicators can be detected compared to the expected values. These disorders of pulmonary ventilation are transient and are caused by the presence of viscous sputum in the lumen of the respiratory tract, as well as bronchial hyperreactivity and a tendency to moderate bronchospasm, which are completely relieved after the activity of the inflammatory process in the bronchi subsides.
According to L.P. Kokosov et al. (2002) and N.A. Savinov (1995), such patients with functionally unstable bronchitis should be classified as a risk group, since over time they develop obstructive ventilation disorders much more often. It is possible that the described bronchial hyperreactivity and their functional destabilization during an exacerbation of bronchitis are based on a persistent viral infection (flu, RS-virus or adenovirus infection).
Bronchoscopy
The need for endoscopic examination in patients with chronic non-obstructive bronchitis may arise during a period of severe exacerbation of the disease. The main indication for bronchoscopy in patients with chronic non-obstructive bronchitis is the suspicion of purulent endobronchitis. In these cases, the condition of the bronchial mucosa, the nature and prevalence of the inflammatory process, the presence of mucopurulent or purulent contents in the bronchial lumen, etc. are assessed.
Bronchoscopy is also indicated in patients with a painful paroxysmal whooping cough, the cause of which may be hypotonic tracheobronchial dyskinesia of grade II-III, accompanied by expiratory collapse of the trachea and large bronchi, which contributes to the development of obstructive ventilation disorders in a small proportion of patients with chronic non-obstructive bronchitis and maintains purulent inflammation of the bronchi.
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