Bronchiectasis

Introduction to bronchiectasis Bronchiectasis is characterized by an irreversible anatomical abnormality of the local bronchus due to chronic suppurative inflammation and fibrosis of the bronchus and surrounding lung tissue, which destroys the muscles and elastic tissues of the bronchial wall, resulting in bronchial deformation and persistent expansion. The clinical symptoms include chronic cough, massive cyanosis and repeated hemoptysis. The main pathogenic factors are bronchial infection, obstruction and traction. Some have congenital genetic factors. Patients have childhood history of measles, whooping cough or bronchial pneumonia. The improvement of people's lives, the vaccination against measles, whooping cough vaccine, and the use of antibiotics have significantly reduced the disease. basic knowledge The proportion of sickness: 0.6% Susceptible people: no specific population Mode of infection: non-infectious Complications: pneumonia, lung abscess, empyema, pulmonary hypertension, chronic pulmonary heart disease

Cause of bronchiectasis

Infection (30%):

Infection is the most common cause of bronchiectasis. Tuberculosis, whooping cough, adenovirus pneumonia can be secondary to bronchiectasis. Aspergillus and mycoplasma, as well as pathogens that can cause chronic necrotizing bronchopneumonia, can also be secondary to bronchiectasis.

Immune Deficiency (20%):

Defects in one or more immunoglobulins can cause bronchiectasis, and one or more IgG subclasses are often associated with recurrent respiratory infections that can cause bronchiectasis. IgA deficiency is not often associated with bronchiectasis, but it can coexist with IgG2 subtype defects, causing repeated suppurative infection and bronchiectasis in the lungs.

Congenital and hereditary diseases (25%):

The most common hereditary disease causing bronchiectasis is cystic fibrosis. In addition, it may be due to the weak development of connective tissue, which can also cause bronchiectasis.

Ciliary abnormalities (10%):

Abnormal cilia structure and function are important causes of bronchiectasis. Kartagener syndrome manifests as a triad, visceral transposition, sinusitis, and bronchiectasis. The disease is accompanied by abnormal cilia function.

Foreign body inhalation (15%):

Long-term presence of foreign bodies in the airways can lead to chronic obstruction and inflammation, secondary to bronchiectasis.

Pathogenesis

According to its morphology, bronchiectasis can be divided into columnar, saclike and mixed, congenital mostly cystic, secondary mostly columnar, columnar dilated wall damage is light, bronchial appearance is regular, tube diameter is not significantly increased, Only at the end of the square expansion, as the disease progresses, bronchial inflammation spreads to the peripheral lung tissue, causing its destruction and fibrosis, forming a saclike dilatation at the distal end, which is honeycomb-shaped, often with sputum retention and secondary infection. The cyst is further enlarged, and inflammation spreads to the adjacent lung parenchyma, causing varying degrees of pneumonia, small abscesses and lobular atelectasis.

Bronchiectasis is more common in the lower lobe. The lower left bronchus is relatively slender. It has a large angle with the main bronchus and is affected by the heart and blood vessels. The drainage is not smooth and the chance of infection is more. Therefore, the left lower lobe bronchiectasis is more common than the right lower lobe. The bronchial opening of the left tongue is close to the bronchus of the lower back of the lower lobe, which is susceptible to the infection of the lower lobe. Therefore, the left lower lobe and the lobes of the lingual lobe often expand at the same time. The bronchial opening of the right middle lobe is relatively thin. There are three groups of lymph nodes in the front and outside. Therefore, in non-specific or tuberculous infections, the lymph nodes often enlarge, compressing the right middle bronchus, causing obstruction of atelectasis, followed by bronchiectasis, called mid-leaf syndrome.

The small pulmonary artery in the bronchodilatation site often has thrombosis, so that part of the blood in the lesion area is supplied by the bronchial artery. Branches of the pulmonary artery and bronchial artery often expand, and the distortion and anastomotic branch increase, forming a small hemangioma under the mucosa of the wall. Damaged, ruptured and become the pathological basis of bronchiectasis hemoptysis.

The pathophysiological changes of bronchiectasis depend on the extent and nature of the lesions. Because the lungs have great reserve power, such as lesions are limited, they have no effect on the body, respiratory function can generally be unchanged, and columnar expansion has little effect on respiratory function. The cystic dilatation is complicated by obstructive emphysema. If the lesion is more extensive, it is mainly obstructive ventilatory disorder, lung volume is reduced, gas flow rate is decreased, inhaled gas distribution is uneven, physiological shunt is increased, and ventilation/blood flow Proportional imbalance, the bronchial artery and pulmonary artery anastomosis in the lesion area increased, the traffic branch is open, the anatomical shunt of the lung is also increased, often leading to hypoxemia, respiratory failure, advanced disease, extensive destruction of alveolar capillaries, increased pulmonary circulation resistance, At the same time, hypoxemia worsens, eventually leading to pulmonary hypertension, pulmonary heart disease, and even heart failure.

Bronchiectasis prevention

Active treatment of respiratory infections such as sinusitis, tonsillitis, etc. In particular, it is important to prevent the occurrence of measles, hunger cough, bronchial pneumonia, lung abscess and tuberculosis in childhood, and to prevent the occurrence of bronchiectasis. For patients with bronchiectasis, inhaled toxic smoke, harmful dust, etc. It has the effect of reducing the severity of bronchiectasis.

Bronchiectasis complications Complications Pneumonia, lung abscess, empyema, pulmonary hypertension, chronic pulmonary heart disease

Bronchiectasis often causes pneumonia, lung abscess, lung gangrene, empyema, and pneumothorax due to concurrent pyogenic infection. When the lung tissue is extensively fibrotic and the pulmonary capillary bed is severely damaged, the pulmonary circulatory resistance may increase. , pulmonary hypertension, causing chronic pulmonary heart disease.

Bronchiectasis symptoms Common symptoms Weakness of the lungs texture thickening wet Luoyin purulent menstruation delayed appetite loss chest tightness urgency hemoptysis dyspnea

The course of bronchiectasis is mostly chronic and can occur at any age. The onset can often be traced back to childhood with measles, history of pertussis or post-flu pneumonia, or history of tuberculosis, endobronchial tuberculosis, pulmonary fibrosis, etc. It occurs only a few years later. The typical symptoms are chronic cough, coughing a lot of purulent sputum and repeated hemoptysis. Cough is up in the morning, evening and bedtime, up to 100-400ml per day. Many patients have almost no cough at other times, coughing. The patient feels relaxed when it is unobstructed.

The sputum drainage is not smooth, the chest is stuffy, the systemic symptoms are also obviously aggravated, the sputum is mostly yellow-green pus-like, and the anaerobic bacteria can be odorous when collected. The whole day is quietly placed in a glass bottle, and can be divided in a few hours. It is 3 layers: the upper layer is foam, the middle layer is yellow-green turbid pus, the lower layer is necrotic tissue sediment, 90% of patients often have hemoptysis, varying degrees, hemoptysis and severity of disease, the lesion range is not necessarily parallel, some patients, Hemoptysis may be its first and only complaint, clinically known as "dry bronchiectasis", common in tuberculous bronchiectasis, lesions in the upper bronchus, if repeated secondary infections, systemic toxic symptoms can occur, patients There are fever, night sweats, fatigue, loss of appetite, weight loss, etc. When the bronchiectasis is complicated by compensatory or obstructive emphysema, the patient may have difficulty breathing, shortness of breath or cyanosis, and pulmonary heart disease and cardiopulmonary failure may occur in the late stage.

Signs of bronchodilatation are not characteristic, but persistent fixation of wet sputum in any part of the lung may indicate bronchiectasis, emphysema, pulmonary heart disease may have corresponding signs, and some patients (1/3) may have clubbing ( Toe), malnutrition.

Bronchiectasis examination

1, blood test

There is hypoxemia, when the infection is obvious, the white blood cells are elevated, and the nucleus is shifted to the left. The typical sputum can be divided into three layers after being placed for several hours: the upper layer is foam, the middle layer is mucus, and the lower layer is yellow-green purulent and Necrotic tissue, in the presence of anaerobic bacteria, odor, sputum pathogens, susceptibility bacteriological examination, sweat test for cystic fibrosis, serum immunoglobulin assay (B lymphocytes), lymphocytes Counting and skin tests (T lymphocytes), white blood cell counts and classification (phagocytic cells), complement composition determination (CH50, C3, C4).

2, lung function check

One second forced exhalation/forced vital capacity ratio lung function damage is progressive, manifested as obstructive ventilatory disorder, FEV1, FEV1/FVC, PEF decreased, residual gas volume/lung total ratio residual gas accounted for the percentage of total lung volume increased, later Have hypoxemia.

3, X-ray chest

No abnormalities (10%) or increased lung texture, thickening, disordered arrangement, cystic bronchiectasis on the chest radiograph, there are many irregular honeycomb (curly hair) shadows, or round, eggs Round transparent area, even small liquid level, more common in the lung base or near the hilar, columnar bronchiectasis often appears as "orbital sign", that is, two parallel linear shadows appear in the increased texture (central transparent tubular shadow) ).

4, CT examination of the chest

The sensitivity of CT diagnosis of bronchiectasis is 64% to 97%, and the specificity is 93% to 100%. The ability of CT examination to show bronchiectasis depends on the CT scan method, the level of dilated bronchus and the type of bronchiectasis. Bronchiectasis is more reliable than columnar expansion. CT findings of bronchiectasis are associated with type of bronchiectasis, with or without infection and presence or absence of mucus plugs in the lumen:

(1) Columnar bronchiectasis: when accompanied by a mucus plug, it has a columnar or nodular high-density shadow. When there is no mucus in the lumen, the signs of bronchial branching become thinner, and the bronchial diameter is more concomitant. The inner diameter is significantly increased (more than 1.5 times), and the wall thickness can be "orbital sign".

(2) capsular bronchiectasis: it is characterized by a concentrated distribution, a small cavity with a smooth outer surface inside the wall, which can be seen as liquid leveling, also known as "grape cross-marking". When infected, there may be irregular high-density shadows around the lesion. .

(3) bronchial varices: the bronchi is irregularly beaded.

(4) bronchial varicose, close together: lung volume shrinks when the bronchus is close together, compensatory swelling of adjacent lung tissue, high-resolution CT (HRCT) is more sensitive than common CT diagnosis of bronchodilation, and the specificity is higher, especially for clinical suspicious In patients with mild bronchiectasis, the diagnostic accuracy can exceed the bronchoscopy; in addition, HRCT is simple, safe and painless, and can simultaneously observe abnormalities in the bronchial wall and surrounding lung parenchyma, which is incomparable for bronchography. For patients with clinically suspected expansion, the preferred method of diagnosis after chest radiography is HRCT instead of bronchography. When HRCT shows diffuse branching, there is no indication of surgery, bronchography can be completely avoided, when HRCT When negative is shown and clinical symptoms are atypical, bronchiectasis can be completely ruled out, and spiral CT is superior to HRCT in diagnosing the extent of bronchiectasis and distribution in a certain segment of the lung.

5, bronchography

Bronchial lipiodol angiography is a traditional method for the diagnosis of bronchiectasis. It can determine the presence of lesions, determine the location, nature and extent of the lesions. It can provide an important reference for surgical indications and resection range. Control acute inflammation before angiography. , as much as possible to reduce the amount of sputum, post-contrast should be taken in the body position drainage, so that the contrast agent can be discharged in time, recent studies have shown that HRCT or spiral CT examination has replaced the trend of bronchial iodide angiography.

6, bronchoscopy

Fiberoptic bronchoscopy, through the fiberoptic bronchoscope can be clearly dilated, bleeding and obstruction sites, microscopic mucosal congestion can be seen under the microscope, pus out of the affected area, etc., while local lavage can be performed to obtain lavage fluid for smear Gram stain or bacteria Cultivation, to help diagnose and treat, through the bronchial mucosal biopsy can help the diagnosis of cilia dysfunction.

Diagnosis of bronchiectasis

diagnosis

The diagnosis is based on:

1. History of respiratory infections that induce bronchiectasis in childhood, such as measles, history of pertussis after pertussis or influenza, or history of tuberculosis.

2, long-term chronic cough, cough and sputum or repeated hemoptysis.

3, physical examination of the lung auscultation has a fixed, persistent wet voice, clubbing (toe).

4, X-ray examination showed increased lung texture, thickening, disordered arrangement, which can be seen in the shape of curly hair, and the infection appeared small liquid level, CT typical performance is "orbital sign" or "ring sign" or "grape sign", confirmed diagnosis Depending on bronchial lipiodol angiography or HRCT, suspected congenital factors should be examined, such as serum Ig concentration determination, serum -globulin determination, pancreatic function test, nasal or bronchial mucosal biopsy.

Differential diagnosis

1. Chronic bronchitis: more common in middle-aged patients, coughing in the winter and spring, coughing or wheezing, mostly white mucus sputum, may have purulent sputum when infected, acute lungs are scattered at the end of the acute attack The wet and dry voice is different from the fixed wet voice of bronchiectasis. The wet voice of the disease is variability, and the wet voice can disappear after coughing.

2, lung abscess: there is an acute onset process, chills, high fever, when a large amount of purulent cough, body temperature drops, systemic toxic symptoms are relieved, X-ray shows a large piece of dense inflammation shadow, with a cavity and liquid level, acute phase After effective antibiotic treatment, it can completely disappear. Chronic lung abscess has a history of acute lung abscess. It can often be complicated by bronchiectasis. Bronchiectasis can also be complicated by pulmonary abscess. The diagnosis depends on bronchial lipiodol or HRCT.

3, tuberculosis: more low fever, night sweats, general malaise, weight loss and other symptoms of tuberculosis, with cough, cough, hemoptysis, sputum is generally less, the voice is generally located in the lung tip, chest radiograph is mostly patchy infiltration of the lung In the shadow, the Mycobacterium tuberculosis or PCK tuberculosis DNA can be found positive.

4, congenital pulmonary cysts: more than secondary infections after cough, cough, hemoptysis, chest disease after the disease control showed a clear circular shadow with multiple boundaries, thin wall, no infiltration of surrounding lung tissue.

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