I. Overview
Chronic bronchitis is a chronic non-specific inflammation of the trachea, bronchial mucosa and surrounding tissues. Clinical symptoms of cough and sputum are the main symptoms, and the onset lasts for 3 months each year for 2 or more years. Other diseases with symptoms of coughing, coughing and wheezing (such as tuberculosis, pneumoconiosis, lung abscess, heart disease, cardiac insufficiency, bronchiectasis, bronchial asthma, chronic nasopharyngitis, esophageal reflux syndrome and other disorders) need to be further excluded.
Etiology
The etiology of this disease is not fully understood, and may be the result of the long-term interaction of a variety of factors.
1, harmful gases and harmful particles
such as cigarettes, smoke, dust, irritant gases (sulfur dioxide, nitric oxide, chlorine, ozone, etc.).
2.Infection factors
viruses, mycoplasma, bacteria and other infections are one of the important causes of the development of chronic bronchitis.
3, other factors
Immunity, age and climate are all factors related to chronic bronchitis.
III. Clinical manifestations
Slow onset, long duration, repeated acute attacks with aggravation. The main symptoms are cough, sputum, or wheezing. Acute exacerbation refers to the sudden aggravation of cough, sputum and wheezing. The main cause of acute exacerbation is respiratory tract infection, and the pathogens can be viruses, bacteria, mycoplasma and chlamydia, etc.
1.Cough
The cough is usually predominant in the morning, with bouts of coughing or sputum discharge during sleep.
2.Coughing sputum
Generally white mucus and plasma foamy, occasionally with blood. More sputum is excreted in the early morning, and sputum excretion can be stimulated after getting up or changing position.
3.Shortness of breath or shortness of breath
Wheezing is often called wheezing bronchitis, and some of them may be combined with bronchial asthma. In case of emphysema, shortness of breath after work or activity may be observed.
In the early stages, there are no abnormal signs. During acute attacks, dry and wet rales may be heard in the back or at the base of both lungs, which may decrease or disappear after coughing. In case of combined asthma, extensive rales can be heard with prolonged expiratory phase.
4.Examination
1.X-ray examination
There may be no abnormality in the early stage. Repeated attacks cause bronchial wall thickening, infiltration or fibrosis of inflammatory cells in fine bronchi or alveolar interstitium, manifested as thickened and disorganized lung texture, reticulated or striated or speckled shadows, obvious in both lower lung fields.
2.Respiratory function examination
There is no abnormality in the early stage. If there is small airway obstruction, the maximum expiratory flow rate – volume curve at 75% and 50% lung volume, the flow rate is significantly reduced.
3.Blood test
Occasionally high total white blood cells and/or neutrophils may be seen in bacterial infections.
4.Sputum examination
Pathogenic bacteria may be cultured. Smear may reveal gram-positive or gram-negative bacteria, or a large number of destroyed leukocytes and destroyed cupped cells.
V. Diagnosis
Based on cough and sputum, or with wheezing, with onset lasting 3 months per year and for 2 or more consecutive years, and excluding other chronic airway diseases.
Differential diagnosis
1.Cough variant asthma
Characterized by irritating cough, easily induced by dust, fumes, cold air, etc., often with family or personal history of allergic diseases. It is not effective for antibiotic treatment and can be identified by a positive bronchial excitation test.
2. Eosinophilic bronchitis
Similar clinical symptoms, no obvious changes on X-ray or increased lung texture, negative bronchial excitation test, and easy to misdiagnose clinically. An increase in the proportion of eosinophils on induced sputum examination (≥ 3%) can be diagnosed.
3.Pulmonary tuberculosis
There are often symptoms such as fever, malaise, night sweats and wasting. Sputum for antacid bacilli and chest X-ray can be identified.
4.Bronchial lung cancer
Most of them have several years of smoking history, stubborn irritating cough or past history of cough, and recent change of cough nature, often with blood in sputum. Sometimes it manifests as repeated obstructive pneumonia at the same site, which fails to completely subside with antibacterial drug treatment. Sputum exfoliative cytology, chest CT, and fiberoptic bronchoscopy can clarify the diagnosis.
5. Interstitial lung fibrosis
The clinical course is slow, starting with only cough and sputum, and occasionally a feeling of shortness of breath. On close auscultation, a bursting sound (Velcro rales) can be heard in the lower posterior part of the lung. Blood gas analysis shows that the partial pressure of oxygen in arterial blood is reduced, while the partial pressure of carbon dioxide may not be increased.
6.Bronchiectasis
The typical presentation is recurrent copious pus sputum or recurrent hemoptysis, and coarse texture or curly hair in the lung field is common on X-ray chest radiograph. High-resolution spiral CT examination is useful for diagnosis.
VII. Treatment
1.Treatment of acute exacerbation
(1) Control of infection antibacterial drug treatment can be used quinolones, macrolides, β-lactams orally, and intravenous administration when the condition is severe. Such as levofloxacin, azithromycin, if the pathogenic bacteria can be cultured, the antimicrobial drugs can be selected according to the drug sensitivity test.
(2) Suppress cough and expectorant can be tried with compound licorice combination, also can be added with expectorant medicine bromhexine, aminoglutethimide hydrochloride, myrtle oil, dry cough mainly can be used to suppress cough medicine, such as dextromethorphan, etc.
(3) Asthma can be added with antispasmodic and asthma medicine, such as aminophylline, or theophylline controlled release agent, or long-acting β2 agonist plus glucocorticoid inhalation.
2.Treatment in remission
(1) Quit smoking and avoid the inhalation of harmful gases and other harmful particles.
(2) Enhance physical fitness and prevent colds, which is also one of the main elements in the prevention and treatment of chronic bronchitis.
VIII. Prevention
Some patients can be controlled and do not affect work and study; some patients can develop into obstructive lung disease or even pulmonary heart disease with poor prognosis. Changes in lung function in chronic bronchitis should be monitored in order to select an effective treatment plan in time to control the development of the disease.