Chronic bronchitis

Introduction to chronic bronchitis Chronic bronchitis is a chronic, non-specific inflammation of the trachea, bronchial mucosa and surrounding tissues. Clinically, cough, cough or accompanied by repeated attacks such as asthma is the main symptom, which lasts for 3 months every year for more than 2 years. Early symptoms are mild, more than winter attacks, and relieved in spring and summer. In the late stage, the symptoms may be present all year round due to increased inflammation. Its pathological features are bronchial gland hyperplasia and increased mucosal secretion. The condition progresses slowly and often, and obstructive emphysema often occurs. In severe cases, pulmonary hypertension and even pulmonary heart disease often occur. basic knowledge The proportion of illness: 0.31% Susceptible people: no special people Mode of infection: non-infectious Complications: hemoptysis, bronchial asthma, tuberculosis, bronchiectasis, lung cancer, emphysema, pulmonary hypertension

Causes of chronic bronchitis

Smoking (40%):

The main cause of the disease is that cigarettes contain tar, nicotine and hydrogen cyanide and other chemicals, which can damage airway epithelial cells, reduce ciliary movement and reduce macrophage phagocytosis, resulting in decreased airway purification function. Stimulating submucosal receptors, causing parasympathetic function, causing bronchial smooth muscle contraction, resulting in increased airway resistance, increased glandular secretion, goblet cell hyperplasia, bronchial mucosal congestion and edema, mucus accumulation, easy to induce infection, in addition, cigarette smoke It can increase the production of toxic oxygen free radicals, induce the release of protease by neutrophils, inhibit the anti-protease system, destroy the lung elastic fibers, and induce the occurrence of emphysema. The study shows that the prevalence of chronic bronchitis in smokers is lower than that of non-smokers. It is 2 to 8 times higher. The longer the smoke age, the larger the smoke and the higher the prevalence.

Air pollution (10%):

Air pollution harmful gases such as sulfur dioxide, nitrogen dioxide, chlorine and ozone have stimulating and cytotoxic effects on airway mucosal epithelium. It is reported that the acute exacerbation of chronic bronchitis is significantly increased when the smoke or sulphur dioxide in the air exceeds 1000 g/m3. Other dusts such as silica, coal dust, sugar cane, cotton dust, etc. can also stimulate the damage of the bronchial mucosa, causing damage to the lung clearance function and creating conditions for bacterial infection.

Infection factor (35%):

Infection is one of the important factors in the occurrence and development of chronic bronchitis. Virus, mycoplasma and bacterial infection are the main causes of acute exacerbation of the disease. Viral infection is common with influenza virus, rhinovirus, adenovirus and respiratory syncytial virus. Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus are common, and bacterial infection occurs on the basis of damage to the airway mucosa secondary to virus or mycoplasma infection.

Allergic factors (5%):

Patients with wheezing chronic bronchitis have a history of allergies. The positive rate of skin tests induced by various allergens is also high. The number of eosinophils and histamine in sputum and IgE in blood have an increasing tendency. Some patients Serum rheumatoid factor positive and abnormal distribution of T lymphocyte subsets, it is considered that atopy and immune factors are related to the occurrence of this disease, but it is also believed that the specific trait should be the pathogenesis of asthma, such The patient should actually be in the category of asthma or chronic bronchitis with asthma.

Other (5%):

Acute exacerbation of chronic bronchitis is more common in winter, so meteorological factors should be regarded as one of the important factors of the disease. Cold air can stimulate the secretion of mucus in the gland and weaken the ciliary movement, weaken the defense function of the airway, and can also cause bronchi by reflection. Smooth muscle spasm, mucosal vasoconstriction, local blood circulation disorder, is conducive to secondary infection, most patients with this disease have autonomic dysfunction, some patients with parasympathetic hyperfunction, airway responsiveness is higher than normal people, in addition, the elderly adrenal gland Cortical dysfunction, impaired cellular immune function, decreased lysozyme activity, low nutrition, insufficient vitamin A, C, etc. can increase airway mucosal vascular permeability and epithelial repair function, whether genetic factors are related to the pathogenesis of chronic bronchitis So far, there is no definite evidence.

Under normal circumstances, the respiratory tract has a perfect defense function, which can filter, warm and humidify the inhaled air; ciliary movement and cough reflex on the airway mucosa surface, thereby removing foreign matter and pathogenic microorganisms in the airway. There is also secretory IgA in the lower respiratory tract, which has the function of resisting pathogenic microorganisms. Therefore, the lower respiratory tract can generally maintain a purifying state, and the systemic or respiratory local defense and immune function decline, especially in the elderly, it is easy to suffer from chronic bronchitis, and Repeated episodes do not heal.

1. The gonads and adrenal cortex function decline in the elderly, the laryngeal reflex is weakened, the respiratory defense function is degraded, and the function of the mononuclear-phagocytic system is degraded, which may also increase the incidence of chronic bronchitis.

2, nutrition also has a certain impact on bronchitis, vitamin C deficiency, the body's resistance to infection is reduced, vascular permeability is increased; vitamin A deficiency, the bronchial mucosal columnar epithelial cells and mucosal repair function can be weakened, lysozyme activity Reduced, easy to chronic bronchitis.

3, genetic factors related to the incidence of chronic bronchitis, so far has not been confirmed, 1-antitrypsin severely deficient can cause emphysema, but no symptoms of airway disease, suggesting that it is not directly related to chronic bronchitis.

Pathogenesis

Bronchial mucosal epithelial cells degeneration, necrosis, and even shedding to form ulcers, cilia become short, uneven, lodging adhesions, partial complete loss, bronchial endocrine secretions at all levels, mucosal epithelial repair during remission, epithelial thinning, hyperplasia, Squamous metaplasia and granuloma formation, the number of goblet cells increased hypertrophy, the ratio with ciliated cells can be 1:2 (normal 1:4 ~ 5), hypersecretion, thickening or degeneration of basement membrane, bronchial gland Body hypertrophy, the ratio of gland thickness to bronchial wall thickness is often >0.55~0.79 (normal <0.4), the number of mucous acinus is significantly increased compared with serous acinus, and the serous gland can be transformed into mucous gland, mucus acinar hypertrophy, shape Irregular, filled with secretions, it can be seen that the proliferating glands invade the peripheral lymphatic tissue of the cartilage ring.

Various inflammatory cells infiltrate the bronchial wall at all levels, mainly plasma cells, lymphocytes, and sometimes eosinophils. In the acute attack period, a large number of neutrophils can be seen, and acute mucosal inflammation of the mucosal epithelium is severe. Bronchial wall congestion, edema, glandular secretion is more vigorous, chronic bronchitis repeated acute attacks, lesions can be from top to bottom, gradually spread to the bronchioles, infiltration of inflammatory cells in the wall, congestion and edema, mucosal degeneration and necrosis and ulcer formation, Bone granulation tissue and mechanized fibrous tissue hyperplasia lead to stenosis, mucosal epithelial necrosis and destruction of wall inflammation cause local bronchiole collapse, stenosis, distortion, deformation or expansion, and then focal pneumonia, small abscess, Lesions of alveolar wall fibrosis, these lesions also involve the surrounding lung tissue and pleura, causing fibrous tissue hyperplasia and pleural adhesions.

Chronic bronchitis prevention

1. Quit smoking is an important measure to prevent chronic bronchitis.

2. Control occupational or environmental pollution to avoid inhalation of dust, smoke and harmful gases.

3, strengthen exercise, enhance physical fitness, improve immunity and cold tolerance, to prevent colds and respiratory infections, injection of influenza vaccine, pneumococcal vaccine, etc., may have a certain significance for the prevention of susceptible.

4. Regular monitoring of lung function Early detection of airflow limitation and timely measures are also important.

5. Strengthening health education, improving working conditions, health habits and increasing nutrition can play a positive role in preventing chronic bronchitis.

6. Strengthen personal hygiene and avoid contact and inhalation of various predisposing factors.

Chronic bronchitis complications Complications hemoptysis bronchial asthma tuberculosis bronchiectasis lung cancer emphysema pulmonary hypertension

(1) Pulmonary tuberculosis active tuberculosis is often accompanied by symptoms such as hypothermia, fatigue, night sweats, hemoptysis; the degree of cough and sputum is related to the activity of tuberculosis, X-ray examination can find lung lesions, sputum tuberculosis test positive, old tuberculosis The symptoms of toxicity are not obvious, and they are often undetected due to the concealment of chronic bronchitis symptoms. Special attention should be paid.

(3) The age of onset of bronchial asthma is relatively mild, often with a history of individual or family allergic disease; the responsiveness of the trachea and bronchus to various stimuli is increased, manifested as extensive bronchospasm and stenosis, and there is clinically paroxysmal respiration. Difficulties and cough, episodes of short-term or persistent, chest percussion have been unvoiced, auscultation with exhalation prolonged with high-pitched wheezing, late with chronic bronchitis, roar eosinophils in bronchial asthma patients, In patients with wheezing bronchitis, there are fewer sputum.

(3) Bronchiectasis often occurs in children or adolescents, often secondary to measles, pneumonia or whooping cough, repeated recurrent pus and hemoptysis symptoms, wet rales can be heard in the lower part of the lungs, chest X-ray examination of the lower part of the lungs The bronchial shadows are deepened, and the shadows of the lesions are visible in the curls, and the bronchial iodide angiography shows the columnar or cystic bronchiectasis.

(4) Heart disease due to lung stagnation caused by cough, often dry cough, sputum is not much, detailed inquiries can be found in heart disease, shortness of breath, lower extremity edema and other signs of heart disease, signs, X-ray and ECG can help For identification.

(5) Lung cancer occurs in men over 40 years old, long-term smokers, often with blood in the sputum, irritating cough, chest X-ray examination of lungs with block shadows or obstructive pneumonia, sputum exfoliated cells or fiberoptic bronchoscopy Clear diagnosis.

(6) Patients with advanced stage may have emphysema and pulmonary hypertension.

Chronic bronchitis symptoms Common symptoms Two lungs texture thickening Bronchial secretions Increase wheezing cilia Clear dysfunction Blocky sputum Muscle purulent hernia Short wet sputum Repeated atelectasis Chemical bronchitis

1, symptoms

The onset is slow and the course of disease is long. Some patients have acute bronchitis, history of acute respiratory infection such as influenza or pneumonia, and develop this disease due to prolonged unhealed. The main symptoms are chronic cough, cough and shortness of breath or accompanied by Wheezing, the symptoms are initially mild, and as the disease progresses, due to repeated respiratory infections, the acute attacks become more frequent and the symptoms become more serious, especially in winter.

(1) Cough: early morning cough is heavier, daytime is lighter, late night is also obvious, often coughing before going to bed, accompanied by cough, this is due to bronchial mucosal congestion, edema, secretions accumulated in the bronchial cavity As a result, as the disease progresses, the cough does not heal all year round.

(2) Cough: In the morning, there is a lot of sputum sputum. The sputum is generally white mucus or serous foam. Even with blood, this is a slow cough reflex during nighttime sleep, and sputum accumulation in the airway cavity. After getting up, the body position changes due to the change of body position. When the acute attack is accompanied by bacterial infection, the amount of sputum increases, and the sputum becomes sticky or purulent.

(3) shortness of breath and wheezing: the early stage of the disease is not obvious. When the disease progresses with obstructive emphysema, there are gradually different types of shortness of breath, especially after activity. Chronic bronchitis with asthma or so-called asthmatic chronic bronchitis Patients, especially in acute attacks, often have symptoms of wheezing, often accompanied by wheezing.

2, signs

There are no abnormal signs in the early stage, or you can smell dry and wet at the bottom of the lungs. The sound of the sputum can disappear after coughing and sputum sputum. The lung voice can be increased during the acute attack. The number depends on the condition, chronic bronchus Patients with inflammation and asthma can hear a wide range of wheezing and prolonged exhalation in acute episodes. Patients with advanced emphysema often have signs of emphysema, see obstructive emphysema.

3. Classification and staging

(1) Classification: According to the 1979 National Clinical Conference on Chronic Bronchitis, chronic bronchitis was divided into:

1 simple type: in line with the diagnostic criteria of chronic bronchitis, with cough, cough and two symptoms.

2 wheezing type: in line with the diagnostic criteria of chronic bronchitis, with wheezing symptoms, and often or repeatedly wheezing, (currently considered that this type should be chronic bronchitis with asthma).

(2) Staging: According to the progress of the disease, it can be divided into three phases:

1 acute attack period: refers to the emergence of purulent or mucopurulent sputum within 1 week, the amount of sputum increased significantly, or accompanied by fever and other inflammatory manifestations, or cough, phlegm, asthma, any symptoms are significantly increased.

2 Chronic prolongation period: refers to those who have different degrees of cough, expectoration, and asthma symptoms for more than one month.

3 clinical remission period: after treatment or natural remission, the symptoms basically disappeared or occasionally mild cough and a small amount of sputum, for more than 2 months.

Chronic bronchitis examination

1. Classification of white blood cells: The total number of white blood cells and the difference counts in the remission period are normal. The total number of white blood cells and neutrophils may increase in the acute attack period, and the blood eosinophils may increase in patients with asthma.

2, sputum examination: the appearance of sputum in the acute attack is mostly purulent, smear examination can be seen a large number of neutrophils, more eosinophils can be seen in asthma, sputum culture can be seen S. pneumoniae, Haemophilus influenzae And growth of catarrhal bacteria.

3, X-ray examination: no obvious changes in the early stage, repeated acute hair authors can see the texture of the two lungs thickened, disordered, reticular or strip-like and spotted shadows, the following lung fields are obvious, this is due to increased bronchial wall Thick, bronchiole or alveolar interstitial inflammatory cell infiltration or fibrosis.

4, lung function check one second forced expiratory volume and one second forced exhalation / forced lung capacity ratio no more obvious changes in the early stage, when the airflow is blocked, the first second forced expiratory volume (FEV 1) and FEV 1 and vital capacity ( The ratio of VC) or forced vital capacity (FVC) is reduced (<70%). When the small airway is blocked, the flow rate of the maximum expiratory flow rate-capacity curve at 75% and 50% lung capacity can be significantly reduced, and the closed volume can be increased. Big.

Diagnosis and diagnosis of chronic bronchitis

diagnosis

Diagnosis depends mainly on medical history and symptoms. After excluding other heart and lung diseases (such as tuberculosis, pneumoconiosis, bronchial asthma, bronchiectasis, lung cancer, heart disease, cardiac insufficiency, etc., there are clinically chronic or repeated coughs, sputum or With wheezing, the incidence lasts for at least 3 months, and for two consecutive years or more, the diagnosis can be established, such as the annual incidence lasts less than three months, and there is a clear objective basis (such as X-ray, lung function, etc.) Can be diagnosed.

According to clinical manifestations, chronic bronchitis is divided into two types: simple type and wheezing type. The former mainly manifests as repeated cough and sputum; the latter has wheezing symptoms, accompanied by wheezing.

According to the course of the disease, it can be divided into three phases, so that the treatment is focused.

(1) Acute exacerbation refers to the occurrence of purulent or mucopurulent sputum within 1 week, the sputum volume is significantly increased, or accompanied by inflammation such as fever, or "cough", "sputum" or "asthmatic" within 1 week. The symptoms were significantly aggravated, or the severely ill patients were significantly aggravated.

(2) Chronic prolonged period refers to those who have different degrees of "cough", "sputum" and "asthma" symptoms, and are postponed to more than one month.

(3) After treatment or natural remission in the clinical remission period, the symptoms basically disappear or occasionally have a mild cough and a small amount of sputum, which is maintained for more than 2 months.

According to cough, cough or wheezing, the disease lasts for 3 months every year for 2 years or more, and can exclude other heart and lung diseases (such as tuberculosis, pneumoconiosis, asthma, bronchiectasis, lung cancer, lung abscess, chronic nasopharyngeal disease) , heart disease, cardiac insufficiency, etc., can make a diagnosis, such as the annual onset duration of less than 3 months, and a clear objective basis (such as X-ray, lung function, etc.) can also be diagnosed.

Differential diagnosis

1. Bronchiectasis is more common in children or adolescents. It is often secondary to measles, pneumonia or whooping cough, and has a history of cough and recurrent cough. When combined with infection, the amount of sputum increases, and it is purulent or accompanied by fever. During the course of the disease, hemoptysis is often repeated, and the wet snoring sounds that are often audible and difficult to dissipate around the lower part of the lungs. For the severely ill patients, the clubbings (toes) appear on the chest radiographs, and the texture of the lungs in the lower lungs is rough or curled. Or thin-layer high-resolution CT (HRCT) examination can help to confirm the diagnosis.

2, tuberculosis active tuberculosis patients have low fever in the afternoon, weight loss, fatigue, night sweats and other symptoms of poisoning, cough is not much, often hemoptysis, the symptoms of senile tuberculosis are not obvious, often covered by the symptoms of chronic bronchitis Misdiagnosis, tuberculosis lesions can be found on the chest radiograph, and some patients can be positive for tuberculosis test.

3, bronchial asthma is often a family history of atopic or allergic diseases, more than childhood, generally no chronic cough, history of cough, sudden onset of asthma, and seasonal, blood and sputum eosinophils The cells often increase, and can be relieved quickly after treatment. The lungs are full of wheezing, prolonged exhalation, disappeared after remission, and asymptomatic, but airway responsiveness is still high. Patients with chronic bronchitis and asthma have a history. In the middle of cough, cough occurs before wheezing, prolonged and prolonged after a long time, accompanied by wheezing, and cough, cough symptoms are more prominent than wheezing, antiasthmatic drugs are not as effective as asthma.

4, lung cancer occurs in men over 40 years old, and patients with a history of smoking for many years, irritating cough is often accompanied by blood and chest pain in the sputum, chest X-ray examination often has a shadow or recurrent obstructive pneumonia in the lungs, sputum shedding Cell and fiber bronchoscopy and other examinations can confirm the diagnosis.

5, chronic pulmonary fibrosis, chronic cough, a small amount of mucinous non-purulent sputum, progressive dyspnea, both lungs can be heard and cracked vocal (Velcro sound), severe cases of cyanosis and clubbing, see the chest The texture of the middle and lower lung fields and the peripheral parts of the lungs increased and the reticular formation was reticular. In the meantime, diffuse fine spot shadows were seen. Pulmonary function tests showed restrictive ventilatory dysfunction, diffuse function decreased, PaO2 decreased, and lung biopsy was the means of diagnosis.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.