Bronchiectasis (bronchiectasis) - acquired disease characterized by localized chronic suppurative processes in the irreversibly modified (extended, deformed) and functionally inferior bronchus and lung (mainly of the lower divisions).
The independence of bronchiectasis (bronchiectasis) as a separate nosological form until recent years been challenged by some authors. Indeed, by itself, bronchiectasis can be observed in various pathological processes involving long-term ongoing inflammation and fibrosis in bronchopulmonary tissue. Bronchiectasis occurring as a complication or manifestation of another disease, called secondary. Contact bronchiectasis with acute pneumonia, some doctors consider a form of chronic pneumonia, but more often in the literature, there is a persistent tradition of separation bronchiectasis as an independent nosological entity.
Causes of bronchiectasis
Causes of bronchiectasis so far not been sufficiently clarified. Micro-organisms which cause acute respiratory processes in children, which may be complicated by the formation of bronchiectasis (agents of pneumonia, measles, whooping cough, etc.) may be an etiological factor only conditionally, since the vast majority of patients with these acute diseases terminate in complete recovery. Infectious agents causing acute suppurative process in already modified the bronchi (aureus, Streptococcus pneumoniae, Haemophilus influenzae and others), considered as a cause of exacerbations, but not bronchiectasis.
Very important, and perhaps decisive, role in shaping the bronchiectasis is considered to be inferior bronchial tree (congenital "weakness" of bronchial walls, lack of development of smooth muscle, and elastic cartilage, failure of protective mechanisms, promoting the development and chronicity of infection, and so on ..)
The most important role in the causes of the disease is a violation of bronchial patency, causing the violation of their drainage function and delay secretion. In children, the cause of the formation of atelectasis may be compression of the compliant, and probably innate is not full, bronchi, or blockage of their long thick mucous plug with respiratory infections (pneumonia, banal, or basal) or tuberculous bronhoadenite.
There have long noted by pathogenetic link between bronchiectasis and upper respiratory tract (paranasal sinuitami, chronic tonsillitis, adenoids), which are observed in about half of patients with bronchiectasis, particularly in children. This relationship is explained, perhaps, the general failure of protective mechanisms of respiratory tract, as well as the constant mutual infection of the upper and lower respiratory tract, leading to a peculiar vicious circle.
Some importance in the pathogenesis of bronchiectasis is, apparently, expiratory stenosis of the bronchus and trachea.
When bronchiectasis develops a violation of the pulmonary circulation. As shown by angio-graphic studies, the lumen of the bronchial arteries, submucosal layer increases with bronchiectasis in 5 times, and the lumen of the artery-artery anastomoses - 10 - 12 times. This leads to the formation of pulmonary heart disease and there is a hemodynamic effect after pulmonary resection in some patients.
Classification of bronchiectasis
Depending on the form of bronchiectasis bronchiectasis are distinguished: a) cylindrical and b) saccular, c) spindle-shaped and d) are mixed. Between them there are many transitional forms, which assignment to a particular type bronchiectasis is often arbitrary. Bronchiectasis is also divided on the atelektaticheskie and not associated with atelectasis, which is undoubtedly useful in practice.