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bronchiectasis
bron·chi·ec·ta·sis B0500000 (brŏng′kē-ĕk′tə-sĭs)n. Chronic dilatation of the bronchial tubes.
[Greek bronkhia, bronchial tubes (from bronkhos, windpipe) + Greek ektasis, extension (ek-, out; see ecto- + tasis, a stretching, from teinein, ta-, to stretch; see ten- in Indo-European roots).]bronchiectasis (ˌbrɒŋkɪˈɛktəsɪs) n (Pathology) chronic dilation of the bronchi or bronchial tubes, which often become infected[C19: from bronchi- + Greek ektasis a stretching]bron•chi•ec•ta•sis (ˌbrɒŋ kiˈɛk tə sɪs)
n. a chronic disease of the bronchial tubes characterized by distention and paroxysmal coughing. [1875–80; bronchi(a) + Greek éktasis stretching out] Translationsbronchiectasis
bronchiectasis[¦bräŋ·kē′ek·tə·səs] (medicine) Dilation of the bronchi and bronchioles following a chronic inflammatory process or an infection attended by pus formation. bronchiectasis
Bronchiectasis DefinitionBronchiectasis is a condition in which an area of the bronchial tubes is permanently and abnormally widened (dilated), with accompanying infection.DescriptionThe bronchial tubes are the networks of branching tubes which deliver air to the tiny sacs of the lungs (alveoli). In bronchiectasis, the diameter of the bronchi is unusually large. Examination of the walls of the bronchial tubes reveals destruction of the normal structural elements, with replacement by scar tissue. Pus collects within the bronchi, and the normal flow of oxygen into the lungs, and carbon dioxide out of the lungs (air exchange) is impaired. The bronchi show signs of inflammation, with swelling and invasion by a variety of immune cells. The inflamed areas show signs of increased growth of blood vessels. The area of the lung which should be served by a diseased bronchial tube is also prone to inflammation and infection.Causes and symptomsPrior to the widespread use of immunizations, bronchiectasis was often the result of a serious infection with either measles or whooping cough. Currently, viruses that cause influenza (flu) or influenza-like syndromes, as well as a number of bacteria may precede the development of bronchiectasis. Patients who have been infected with tuberculosis or the virus which causes AIDS (HIV or human immunodeficiency virus) also have an increased chance of bronchiectasis.A number of pre-existing conditions may cause an individual to be more susceptible than normal to infection, with increased risk of bronchiectasis developing. These conditions include disorders of cilia, and immune disorders.Cilia are the tiny hairs which usually line the bronchial tubes. Cilia wave constantly, sweeping the bronchial tubes clean of bacterial or viral invaders, and cleaning away excess secretions (mucus, sputum) which may be produced by the bronchi. When these cilia are abnormal or absent at birth, various bacterial or viral invaders may remain in the respiratory tract, multiply, and cause serious infections.Immune disorders include decreased production of certain immune chemicals (immunoglobulins) which usually serve to fight off infection by bacterial or viral invasion. When these immunoglobulins are not produced in large enough quantity, bacterial and viral invaders are not effectively killed off, and infection occurs.Other causes of bronchiectasis include an abnormally blocked (obstructed) airway. This can be due to tumor growth within the bronchial tube, or due to a child accidentally inhaling a small object which then blocks off the bronchial tube. People with the disease called cystic fibrosis (CF) often have their bronchial tubes obstructed by the thick, sticky mucus which is a hallmark of CF. Toxic exposures (breathing ammonia, for example) can harm the bronchi, and lead to bronchiectasis. An extreme allergic response of the immune system to the presence of certain fungi (especially one called Aspergillus) can also damage the bronchial tubes enough to result in bronchiectasis.Symptoms of bronchiectasis include constant cough and the production of infected sputum (sputum is a mixture of mucus and pus), which may be bloody. In some cases, there may be wheezing and shortness of breath. The constant, low-level of infection may flare, resulting in increased production of sputum, worsening of the cough, and fever. The area of the lung served by the affected bronchial tube may become severely infected, resulting in pneumonia.Key termsBronchi — The network of tubular passages which carry air to the lung and allow air to be expelled from the lungs.Cilia — Hair-like projections which line the bronchial tubes (also present in other areas of the body). Normal cilia beat consistently, sweeping the bronchi clean of bacteria, viruses, and mucus.DiagnosisChest x ray may reveal evidence of bronchiectasis, and CT scans are particularly good at revealing the thick, dilated bronchial walls of bronchiectasis. Sputum will need to be collected and cultured (grown in a laboratory dish), in order to examine it microscopically for the specific type of organism responsible for infection. A careful search for other underlying diseases is important, looking in particular for ciliary abnormalities, cystic fibrosis, or immunoglobulin deficiencies.TreatmentTreatment should involve efforts to resolve any underlying disorder. Infections will require antibiotics, obstruction may require the removal of a foreign object or tumor. Medications are available to help thin the sputum, so that it can be more effectively coughed up. Rhythmic clapping on the chest and back, while the patient assumes a number of positions (head down, primarily), may help the lungs to drain more effectively. This is called chest physical therapy, or percussion and postural drainage.When a particular area of the lung is constantly and severely infected, surgery may be needed to remove it. When bleeding occurs from irritated bronchial tubes and overgrown bronchial blood vessels, surgery may be required either to remove an area of the bronchial tube, or to inject the bleeding blood vessel with a material to stop the bleeding.In some patients, bronchiectasis eventually leads to a constantly low level of blood oxygen, despite other treatments. These patients usually have an associated increase in the size of the right side of their hearts, along with a decrease in the heart's ability to pump blood through the lungs. Some patients with extremely severe symptoms and disability have been treated with lung transplantation.PrognosisPrognosis varies widely, depending on how widespread or focal the bronchiectasis, and the presence of other underlying disorders.ResourcesOrganizationsAmerican Lung Association. 1740 Broadway, New York, NY 10019. (800) 586-4872. http://www.lungusa.org.bronchiectasis [brong″ke-ek´tah-sis] chronic dilatation of the bronchi and bronchioles associated with secondary infection; types include cylindrical, follicular, fusiform, saccular, and varicose, named according to the nature of the dilatations. It is associated with chronic copious sputum production, and may be associated with an inherited ciliary dysfunction. The most immediate symptom is persistent coughing with sputum production. In advanced cases the sputum and breath may become foul-smelling, and the patient may suffer loss of appetite, anemia, fever, episodes of pneumonia, and a general lowering of resistance to infection. The principal treatment is chest physical therapy with antibiotics. Long-term care is essentially the same as for any patient with chronic airflow limitation.bron·chi·ec·ta·sis (brong'kē-ek'tă-sis), [MIM*211400] Chronic dilation of bronchi or bronchioles as a sequel of inflammatory disease or obstruction often associated with heavy sputum production. Synonym(s): bronchiectasia [bronchi- + G. ektasis, a stretching] bronchiectasis (brŏng′kē-ĕk′tə-sĭs)n. Chronic dilatation of the bronchial tubes.bronchiectasis Progressive dilatation of bronchi or bronchioles due to pneumonitis, pneumonia, obstruction, tumours or congenital disease—e.g., cystic fibrosis.
Clinical findings
Halitosis, paroxysmal coughing, expectoration of mucopurulent matter; it may affect the bronchioles uniformly (cylindric bronchiectasis), occur in irregular pockets (saccular bronchiectasis) or dilated bronchi may have terminal bulbous enlargements (fusiform bronchiectasis). Bronchiectasis is rarely congenital; it is most often acquired in childhood.bronchiectasis Chest medicine Progressive dilatation of bronchi or bronchioles due to pneumonitis, pneumonia, obstruction, tumors or congenital disease–eg, cystic fibrosis Clinical Halitosis, paroxysmal coughing, expectoration of mucopurulent matter; it may affect bronchioles uniformly–cylindric bronchiectasis, occur in irregular pockets–saccular bronchiectasis or dilated bronchi may have terminal bulbous enlargements–fusiform bronchiectasis; rarely congenital, it is usually acquired in childhoodbron·chi·ec·ta·sis (brong'kē-ek'tă-sis) Chronic dilation of bronchi or bronchioles as a sequel of inflammatory disease or obstruction. bronchiectasis Permanent areas of local widening of the smaller air tubes of the lung (the bronchi) with persistent infection and a tendency to retention of local infected secretions. There is profuse sputum.bron·chi·ec·ta·sis (brong'kē-ek'tă-sis) [MIM*211400] Chronic dilation of bronchi or bronchioles as a sequel of inflammatory disease or obstruction. |