I can't remember the study I read, but it said that "most" (sorry to be vague) people with CF will have radiographic evidence of bronchiectasis by adulthood. And this Australian study of infants and preschoolers showed 22% had bronchiectasis.
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<br /><a target=_blank class=ftalternatingbarlinklarge href="http://www.jpeds.com/article/S0022-3476(09)00474-0/abstract
">http://www.jpeds.com/article/S...6(09)00474-0/abstract
</a><br />
<br />Here is a thorough list of causes for bronchiectasis from Emedicine:
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<br /><b> * Primary infections</b>
<br /> o Bronchiectasis may be the sequela of a variety of necrotizing infections that are either poorly treated or not treated at all and are not occurring in the setting of another associated condition. This was particularly common in developed countries prior to the widespread use of antibiotics25 and today remains an important cause of bronchiectasis in developing countries, where antibiotics are used inconsistently.14,15
<br /> o Typical offending organisms that have been known to cause bronchiectasis include Klebsiella species, Staphylococcus aureus, Mycobacterium tuberculosis, Mycoplasma pneumoniae, nontuberculous mycobacteria, measles virus, pertussis virus, influenza virus, herpes simplex virus, and certain types of adenovirus.7,25
<br /> o Infection with respiratory syncytial virus in childhood may also result in bronchiectasis.
<br /> o MAC infection deserves special mention for its propensity to occur in the setting of human immunodeficiency virus (HIV) and in hosts who are immunocompetent.31 MAC infection has been observed especially in women who are nonsmokers; are older than 60 years; and have a consistent history, positive acid-fast bacilli on sputum smear, and a CT scan with small regular nodules and findings of bronchiectasis.8,11,22
<br /> o Once a patient develops bronchiectasis, many of these same organisms colonize the damaged bronchi and may result in ongoing damage and episodic infectious exacerbations. The organisms found most typically include Haemophilus species (47-55% of patients) and Pseudomonas species (18-26% of patients).32,33
<br /> o Although not a primary cause of bronchiectasis, patients with non-CF bronchiectasis often develop chronic bronchial infection with Pseudomonas aeruginosa via a mechanism involving biofilm formation and the release of virulence factors. This suggests that Pseudomonas species may promote disease progression and may be related to worsening lung function and increased morbidity and mortality.34
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<br /> * Bronchial obstruction</b>
<br /> o Focal postobstructive bronchiectasis may occur in a number of clinical settings (eg, endobronchial tumors, broncholithiasis, bronchial stenosis from infections, encroachment of hilar lymph nodes, foreign body aspiration).
<br /> o Right-middle lobe syndrome is a specific type of bronchial obstruction that may result in bronchiectasis. It results from an abnormal angulation of the lobar bronchus at its origin, predisposing it to obstruction, subsequent infection, and development of bronchiectasis.
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<br /> * Aspiration </b>
<br /> o In adults, foreign body aspiration often takes place in the setting of altered mental status and involves unchewed food. Patients may also aspirate chewed materials from the stomach, including food, acid, and microorganisms.
<br /> o After aspiration, a postobstructive pneumonia may occur, with subsequent development of focal bronchiectasis. Bronchiectasis may also develop in the setting of chronic aspiration. Further recognized is that a history of gastroesophageal reflux is a risk factor for aspiration and that the organism Helicobacter pylori may be playing a role in the development of bronchiectasis in this group of patients.35,36,37
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<br /> * Cystic fibrosis</b>
<br /> o CF and its variants are likely the most common cause of bronchiectasis in the United States and other industrialized nations. CF is an autosomal recessive disease affecting approximately 1 in 2,500 whites and 1 in 17,000 blacks in the United States.38 Estimates indicate 10,000 adults in the United States in 2005 would have CF, and this would comprise 40% of the total CF population.39
<br /> o CF is a multisystem disorder that affects the chloride transport system in exocrine tissues, primarily secondary to a defect in the CF transmembrane regulator (CFTR) protein. Multiple genetic variants exist, and the importance of patients that have genetic heterozygous mutations remains to be elucidated. However, a reasonable assumption is that CF can be divided into 2 groups of patients: (1) those with classic disease that is readily diagnosed based on clinical and laboratory data and (2) those with less severe disease that manifests later in life and who have ambiguous genetic testing results.40,41,42
<br /> o The major pulmonary finding in CF is bronchiectasis, which is an almost universal feature of this disease. It may be the sole feature of CF in adults or those with genetic variations of the disease.
<br /> o Bronchiectasis associated with CF is believed to occur secondary to mucous plugging of proximal airways and chronic pulmonary infection, especially with mucoid P aeruginosa.43
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<br /> * Young syndrome44</b>
<br /> o Young syndrome is clinically similar to CF and may represent a genetic variant of the disease. It is most commonly seen in North American males and is a leading cause of male infertility.
<br /> o Patients have bronchiectasis (often predominant in the lower lobes), sinusitis, and obstructive azoospermia, but they are not affected with the other findings of CF.
<br /> o It is most often observed in middle-aged men.
<br /> o The pathogenesis of bronchiectasis is believed to be similar to that of CF.
<br /> o The criterion standard for diagnosis is electron microscopic analysis of the structure of the cilia.
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<br /><b> * Primary ciliary dyskinesia
<br /></b> o Primary ciliary dyskinesia is a group of inherited disorders that may affect 1 in 15,000-30,000 persons. It is manifested by immotile or dyskinetic cilia and/or sperm. This may lead to poor mucociliary clearance, recurrent pulmonary infections, and, ultimately, bronchiectasis.45,46
<br /> o A variant of this condition, initially described by Kartagener, encompassed the clinical triad of situs inversus, nasal polyps or sinusitis, and bronchiectasis in the setting of immotile cilia of the respiratory tract.47
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<br /> <b>* Allergic bronchopulmonary aspergillosis48
<br /></b> o Allergic bronchopulmonary aspergillosis (ABPA) is a hypersensitivity reaction to inhaled Aspergillus antigen that is characterized by bronchospasm, bronchiectasis, and immunologic evidence of a reaction to Aspergillus species.
<br /> o ABPA should be suspected in patients with a productive cough who also have a long history of asthma-type symptoms that do not respond to conventional therapy.
<br /> o Bronchiectasis is believed to be secondary to airway plugging by viscid secretions containing hyphae of Aspergillus species. The resulting bronchiectasis is thin-walled and affects the central and medium-sized airways.
<br /> o CT scanning of the chest exhibits central airway bronchiectasis, differentiating this condition from other causes of bronchiectasis.
<br /> o Other features of ABPA include eosinophilia, elevated immunoglobulin E (IgE) levels, and dramatic responses to corticosteroids.
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<br /><b> * Immunodeficiency states
<br /></b> o Immunodeficiency states may occur in the setting of congenital and acquired immunodeficiency. The most common congenital conditions (albeit rare) involve B-lymphocyte functions, specifically hypogammaglobulinemia. The latter may involve an immunoglobulin G (IgG) subclass deficiency; X-linked agammaglobulinemia; or selective immunoglobulin A (IgA), immunoglobulin M (IgM), or IgE deficiency.49,50,51,52
<br /> o Patients with hypogammaglobulinemia usually present in childhood with repeated sinus or pulmonary infections, although it has been diagnosed in adults who did not have a history of repeated infections. Establishing the diagnosis is important because gammaglobulin replacement may reduce the number of infections and resultant lung injury.
<br /> o HIV disease, with resultant acquired immunodeficiency syndrome (AIDS), has been implicated in the development of bronchiectasis and demonstrates the accelerated bronchial damage that may occur from repeated infections in patients who are immunosuppressed. Bronchiectasis in HIV infection has occurred with and without obvious preceding pulmonary infection and may occur secondary to immunologic dysfunction from the HIV disease itself.31,53,54
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<br /> <b>* Congenital anatomic defects and connective-tissue disorders</b>
<br /> o Bronchopulmonary sequestration is a congenital abnormality classified as either intralobar or extralobar and results in chronic lower respiratory tact infections that lead to bronchiectasis.
<br /> o Williams-Campbell syndrome (congenital cartilage deficiency) is the absence of cartilage from lobar to first- to second-generation segmental airways that results in extensive peripheral bronchiectasis.55
<br /> o Mounier-Kuhn syndrome (tracheobronchomegaly) is a rare disorder characterized by dilation of the trachea and segmental bronchi (central bronchiectasis).56
<br /> o Swyer-James syndrome (unilateral hyperlucent lung) likely is a developmental disturbance that leads to unilateral bronchiolitis, hyperinflation, and, in some cases, bronchiectasis.
<br /> o Yellow-nail syndrome57
<br /> o Marfan syndrome is a connective-tissue disorder in which the general consensus is weakness of the connective tissue of the bronchial wall predisposes to bronchiectasis.58
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<br /><b> * Alpha1-antitrypsin (AAT) deficiency59
<br /></b> o Bronchiectasis has been noted to occur in this rare condition, both in patients with true AAT deficiency and in patients with heterozygous phenotypes.60,61,62
<br /> o The pathogenesis of bronchiectasis in this setting is unclear, but it is believed that the AAT abnormalities make patients more susceptible to respiratory tract infections and subsequent bronchial damage.
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<br /><b> * Autoimmune diseases and idiopathic inflammatory disorders
<br /></b> o Rheumatoid arthritis is associated with bronchiectasis in a reported 3.2-35%63,64,65,66 and, in one series, was associated with an unfavorable prognosis.67 The pathology of bronchiectasis may be increased susceptibility to infections in these patients. Pulmonary disease may occur prior to the onset of the rheumatic process.
<br /> o With Sjögren syndrome, bronchiectasis has been noted in these patients and may be secondary to increased viscosity of mucus with poor airway clearance.68
<br /> o Ankylosing spondylitis is associated with bronchiectasis, but in small numbers.69
<br /> o Systematic lupus erythematosus may present with a variety of pulmonary pathology, including bronchiectasis, which was reported in 21% of patients in one series.70
<br /> o In relapsing polychondritis, bronchiectasis appears to be secondary to primary bronchial damage with resultant recurrent infection.71
<br /> o With inflammatory bowel disease, bronchiectasis has been seen in both ulcerative colitis and Crohn disease. The etiology remains unclear. Pulmonary symptoms may occur prior to the onset of bowel disease.72
<br /> o Sarcoidosis may cause bronchiectasis by a variety of mechanisms, including parenchymal scarring, endobronchial granulomatous inflammation, or extrinsic compression of bronchi.73
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<br /> <b>* Traction bronchiectasis: </b>Traction bronchiectasis is distortion of the airways secondary to mechanical traction on the bronchi from fibrosis of the surrounding lung parenchyma. Although the airways may become dilated in this situation, the other manifestations of bronchiectasis are lacking.
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<br /><b> * Toxic gas exposure: </b>Exposure to toxic gas may often cause irreversible damage to the bronchial airways and cystic bronchiectasis. Commonly suspected agents include chlorine gas and ammonia.
