Bronchiectasis

Template:Short description Template:Infobox medical condition (new) Bronchiectasis is a disease in which there is permanent enlargement of parts of the airways of the lung.<ref name=NIH2014What>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Symptoms typically include a chronic cough with mucus production.<ref name=Mc2013>Template:Cite journal</ref> Other symptoms include shortness of breath, coughing up blood, and chest pain.<ref name=NIH2014Sign>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Wheezing and nail clubbing may also occur.<ref name=NIH2014Sign/> Those with the disease often get lung infections.<ref name=NIH2014Tx>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Bronchiectasis may result from a number of infectious and acquired causes, including measles,<ref>Template:Cite news</ref> pneumonia, tuberculosis, immune system problems, as well as the genetic disorder cystic fibrosis.<ref>Template:Cite journal</ref><ref name=Mc2013/><ref name=DAVIDSONS2010>Template:Cite book</ref> Cystic fibrosis eventually results in severe bronchiectasis in nearly all cases.<ref>Template:Cite book</ref> The cause in 10–50% of those without cystic fibrosis is unknown.<ref name=Mc2013/> The mechanism of disease is breakdown of the airways due to an excessive inflammatory response.<ref name=Mc2013/> Involved airways (bronchi) become enlarged and thus less able to clear secretions.<ref name=Mc2013/> These secretions increase the amount of bacteria in the lungs, resulting in airway blockage and further breakdown of the airways.<ref name=Mc2013/> It is classified as an obstructive lung disease, along with chronic obstructive pulmonary disease and asthma.<ref>Template:Cite book</ref> The diagnosis is suspected based on symptoms and confirmed using computed tomography.<ref name=BTS2012>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Cultures of the mucus produced may be useful to determine treatment in those who have acute worsening and at least once a year.<ref name=BTS2012/>

Periods of worsening may occur due to infection.<ref name=NIH2014Tx/> In these cases, antibiotics are recommended.<ref name=NIH2014Tx/> Common antibiotics used include amoxicillin, erythromycin, or doxycycline.<ref>Template:Cite book</ref> Antibiotics, such as erythromycin, may also be used to prevent worsening of disease.<ref name=Mc2013/><ref name=Qi2014>Template:Cite journal</ref> Airway clearance techniques, a type of physical therapy, are also recommended.<ref name=Lee2015>Template:Cite journal</ref> Medications to dilate the airways and inhaled steroids may be used during sudden worsening, but there are no studies to determine effectiveness.<ref name=Mc2013/><ref name=":3">Template:Cite journal</ref> There are also no studies on the use of inhaled steroids in children.<ref name=":3" /> Surgery, while commonly done, has not been well studied.<ref>Template:Cite journal</ref><ref name=Mc2013/> Lung transplantation may be an option in those with very severe disease.<ref name=Cor2013>Template:Cite journal</ref>

The disease affects between 1 per 1000 and 1 per 250,000 adults.<ref name=Cot2015>Template:Cite book</ref> The disease is more common in women and increases as people age.<ref name=Mc2013/> It became less common since the 1950s with the introduction of antibiotics.<ref name=Cot2015/> It is more common among certain ethnic groups (such as indigenous people in the US).<ref name=Cot2015/> It was first described by René Laennec in 1819.<ref name=Mc2013/> The economic costs in the United States are estimated at $630 million per year.<ref name=Mc2013/>

Signs and symptoms

File:Depiction of a person suffering from Bronchiectasis.png

The typical symptoms of bronchiectasis are shown. Also, the change in bronchi under bronchiectasis are illustrated.

Symptoms of bronchiectasis commonly include a cough productive of frequent green or yellow sputum lasting months to years.<ref name="Mc2013" /> Other common symptoms include difficulty breathing, wheezing (a whistling sound when you breathe), and chest pain. Exacerbations of symptoms may occur, these exacerbations occur more frequently in advanced or severe disease.<ref name="O'Donnell NEJM" /> Systemic symptoms, including fevers, chills, night sweats, fatigue and weight loss may be seen with bronchiectasis.<ref name="O'Donnell NEJM" /> Bronchiectasis may also present with coughing up blood in the absence of sputum, which has been called "dry bronchiectasis."

Exacerbations in bronchiectasis present as a worsening of cough, increasing sputum volume or thickened consistency lasting at least 48 hours, worsening shortness of breath (breathlessness), worsening exercise intolerance, increased fatigue or malaise and the development of hemoptysis.<ref name="O'Donnell NEJM" />

People often report frequent bouts of "bronchitis" requiring therapy with repeated courses of antibiotics. People with bronchiectasis may have bad breath from active infection. On examination, crepitations and expiratory rhonchi may be heard with auscultation. Nail clubbing is a rare symptom.<ref name="Mc2013" />

The complications of bronchiectasis include serious health conditions, such as respiratory failure and atelectasis: collapse or closure of a lung. Respiratory failure occurs when not enough oxygen passes from the lungs into the blood.<ref name=":4">{{#invoke:citation/CS1|citation |CitationClass=web }} Template:PD-notice</ref> Atelectasis occur when one or more segments of the lungs collapse or do not inflate properly. Other pulmonary complications include lung abscess and empyema. Cardiovascular complications include cor pulmonale, in which there is enlargement and failure of the right side of the heart as a result of disease of the lungs.<ref>Template:EMedicine</ref>

Causes

Category	Causes
Autoimmune disease	Rheumatoid arthritis Sjögren syndrome
Impaired host defenses	Cystic fibrosis Primary ciliary dyskinesia Primary immunodeficiency HIV/AIDS Job's syndrome
Post-infective	Bacterial pneumonia Mycobacterium infection Viral infection
Congenital	Tracheobronchomegaly Marfan syndrome Williams–Campbell syndrome Young's syndrome Alpha-1 antitrypsin deficiency
Hypersensitivity	Allergic bronchopulmonary aspergillosis
Inflammatory bowel disease	Ulcerative colitis Crohn's disease
Malignancy	Chronic lymphocytic leukemia Graft-versus-host disease
Obstruction	Tumor Foreign body aspiration Lymphadenopathy
Other	Pneumonia Chronic aspiration Ammonia inhalation Smoke inhalation Radiation-induced lung disease Yellow nail syndrome

There are many causes that can induce or contribute to the development of bronchiectasis. The frequency of these different causes varies with geographic location.<ref name="auto">Template:Cite journal</ref> Cystic fibrosis is identified as a cause in up to half of cases.<ref name=Mc2013/> Bronchiectasis without CF is known as non-CF bronchiectasis. Historically, about half of all cases of non-CF bronchiectasis were found to be idiopathic, or without a known cause.<ref>Template:Cite journal</ref> However, more recent studies with a more thorough diagnostic work-up have found an etiology in 60 to 90% of patients.<ref name="auto" /><ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>

Cystic fibrosis

Cystic fibrosis is the most common life-threatening autosomal recessive disease in the United States and Europe.<ref name="auto3">Template:Cite journal</ref> It is a genetic disorder that affects the lungs, but also the pancreas, liver, kidneys, and intestine.<ref>Template:Cite journal</ref> It is caused by mutations in the CFTR protein, a chloride channel expressed in epithelial cells.<ref name="auto3" /> Lung disease results from clogging of the airways due to mucus build-up, decreased mucociliary clearance, and resulting inflammation.<ref>Template:Cite journal</ref> In later stages, changes to the structure of the lung, such as bronchiectasis, occur.

Airway obstruction

An airway obstruction can be caused by either an intraluminal mass such as a tumor or a foreign body.<ref name="Kwon 302–307">Template:Cite journal</ref> The presence of an airway obstruction leads to a cycle of inflammation.<ref name=Mc2013/> It is important to identify the presence of an obstruction because surgical resection is often curative if obstruction is the cause.<ref>Template:Cite journal</ref> In adults, foreign body aspiration is often associated with an altered state of consciousness. The foreign body is often unchewed food, or part of a tooth or crown.<ref>Template:Cite journal</ref> Bronchiectasis that results from foreign body aspiration generally occurs in the right lung in the lower lobe or posterior segments of the upper lobe.<ref name=":6">Template:EMedicine</ref>

Lung infections

A range of bacterial, mycobacterial, and viral lung infections are associated with the development of bronchiectasis. Bacterial infections commonly associated with bronchiectasis include P. aeruginosa, H. influenzae, and S. pneumoniae.<ref name="Mc2013" /> Gram-negative bacteria are more commonly implicated than gram-positive bacteria.<ref name="Mc2013" /> A history of mycobacterial infections such as tuberculosis can lead to damage of the airways that predisposes to bacterial colonization.<ref>Template:Cite journal</ref> Severe viral infections in childhood can also lead to bronchiectasis through a similar mechanism.<ref>Template:Cite journal</ref> Nontuberculous mycobacteria infections such as Mycobacterium avium complex are found to be a cause in some patients.<ref>Template:Cite journal</ref> Recent studies have also shown Nocardia infections to been implicated in bronchiectasis.<ref>Template:Cite journal</ref>

Impaired host defenses

Impairments in host defenses that lead to bronchiectasis may be congenital, such as with primary ciliary dyskinesia, or acquired, such as with the prolonged use of immunosuppressive drugs.<ref name=":02">Template:Cite journal</ref> Additionally, these impairments may be localized to the lungs, or systemic throughout the body. In these states of immunodeficiency, there is a weakened or absent immune system response to severe infections that repeatedly affect the lung and eventually result in bronchial wall injury.<ref>Template:Cite journal</ref> HIV/AIDS is an example of an acquired immunodeficiency that can lead to the development of bronchiectasis.<ref>Template:Cite journal</ref>

Aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is an inflammatory disease caused by hypersensitivity to the fungus Aspergillus fumigatus.<ref>Template:Cite journal</ref> It is suspected in patients with a long history of asthma and symptoms of bronchiectasis such as a productive, mucopurulent cough.<ref>Template:Cite journal</ref> Imaging often shows peripheral and central airway bronchiectasis, which is unusual in patients with bronchiectasis caused by other disorders.<ref>Template:Cite journal</ref>

Autoimmune diseases

Several autoimmune diseases have been associated with bronchiectasis. Specifically, individuals with rheumatoid arthritis and Sjögren syndrome have increased rates of bronchiectasis.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> In these diseases, the symptoms of bronchiectasis usually presents later in the disease course.<ref>Template:Cite journal</ref> Other autoimmune diseases such as ulcerative colitis and Crohn's disease also have an association with bronchiectasis.<ref>Template:Cite journal</ref> Additionally, graft-versus-host disease in patients who have undergone stem cell transplantation can lead to bronchiectasis as well.<ref name=":02" />

Lung injury

Bronchiectasis could be caused by: inhalation of ammonia and other toxic gases,<ref>Template:Cite journal</ref> chronic pulmonary aspiration of stomach acid from esophageal reflux,<ref name="lietal">Template:Cite journal</ref> or a hiatal hernia.<ref name="lietal" />

Congenital

Bronchiectasis may result from congenital disorders that affect cilia motility or ion transport.<ref name="DAVIDSONS20102">Template:Cite book</ref> A common genetic cause is cystic fibrosis, which affects chloride ion transport.<ref name="auto3" /> Another genetic cause is primary ciliary dyskinesia, a rare disorder that leads to immotility of cilia and can lead to situs inversus.<ref>Template:Cite journal</ref> When situs inversus is accompanied by chronic sinusitis and bronchiectasis, this is known as Kartagener's syndrome.<ref>Template:Cite journal</ref> Other rare genetic causes include Young's syndrome<ref>Template:Cite journal</ref> and Williams-Campbell syndrome.<ref name="pmid138448572">Template:Cite journal</ref> Tracheobronchomegaly, or Mournier-Kuhn syndrome is a rare condition characterized by significant tracheobronchial dilation and recurrent lower respiratory tract infections.<ref>Template:Cite journal</ref> Individuals with alpha 1-antitrypsin deficiency have been found to be particularly susceptible to bronchiectasis, due to the loss of inhibition to enzyme elastase which cleaves elastin.<ref>Template:Cite journal</ref> This decreases the ability of the alveoli to return to normal shape during expiration.<ref>Template:Cite journal</ref>

Cigarette smoking

A causal role for tobacco smoke in bronchiectasis has not been demonstrated.<ref name=":02" /> Nonetheless, tobacco smoking can worsen pulmonary function and accelerate the progression of disease that is already present.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>

Pathophysiology

File:Bronchiectasis Vicious Cycle Pathogenesis.png

"Vicious cycle" theory of the pathogenesis of bronchiectasis.

The development of bronchiectasis requires two factors: an initial injury to the lung (such as from infection, auto-immune destruction of lung tissue, or other destruction of lung tissue (as seen in gastroesophageal reflux disease or aspiration syndromes)) which leads to impaired mucociliary clearance, obstruction, or a defect in host defense.<ref name="O'Donnell NEJM" /><ref name="Mc2013" /> This triggers a host immune response from neutrophils (elastases), reactive oxygen species, and inflammatory cytokines that results in progressive destruction of normal lung architecture. In particular, the elastic fibers of bronchi are affected.<ref name="DAVIDSONS2010" /> The result is permanent abnormal dilation and destruction of the major bronchi and bronchiole walls.<ref name="Bronchiectasis">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Disordered neutrophil function is believed to play a role in the pathogenesis of bronchiectasis. Neutrophil extracellular traps (NETs), which are extracellular fibers secreted by neutrophils that are used to trap and destroy pathogens, are hyperactive in bronchiectasis. Increased NET activity is associated with more severe bronchiectasis.<ref name="O'Donnell NEJM" /> Neutrophil elastase, which is an extracellular protein secreted by neutrophils to destroy pathogens as well as host tissue, is also hyperactive in many cases of bronchiectasis.<ref name="O'Donnell NEJM" /> An increased neutrophil elastase activity is also associated with worse outcomes and more severe disease in bronchiectasis.<ref name="O'Donnell NEJM" /> The initial lung injury in bronchiectasis leads to an impaired mucociliary clearance of the lung airways, which leads to mucous stasis.<ref name="O'Donnell NEJM" /> This mucous stasis leads to bacterial colonization in bronchiectasis which leads to neutrophil activation.<ref name="O'Donnell NEJM" /> This neutrophil activation leads to further tissue destruction and airway distortion by neutrophils in addition to direct tissue destruction by the pathogenic bacteria.<ref name="O'Donnell NEJM" /> The distorted, damaged lung airways thus have impaired mucociliary clearance; leading to mucous stasis and bacterial colonization leading to further neutrophil activation and thus fueling a self-perpetuating "vicious cycle" of inflammation in bronchiectasis.<ref name="O'Donnell NEJM" /> This "vicious cycle" theory is the generally accepted explanation for the pathogenesis of bronchiectasis.<ref name=":02"/>

Endobronchial tuberculosis commonly leads to bronchiectasis, either from bronchial stenosis or secondary traction from fibrosis.<ref name=":6"/> Traction bronchiectasis characteristically affects peripheral bronchi (which lack cartilage support) in areas of end-stage fibrosis.<ref name=":7">Template:EMedicine</ref>

Diagnosis

File:Bronquiectasia.jpeg

CT scan of the lungs showing findings diagnostic of bronchiectasis. White and black arrows point to dilated bronchi characteristic of the disease.

The goals of a diagnostic evaluation for bronchiectasis are radiographic confirmation of the diagnosis, identification of potential treatable causes, and functional assessment of the patient. A comprehensive evaluation consists of radiographic imaging, laboratory testing, and lung function testing.<ref name="Pasteur i1–58">Template:Cite journal</ref>

Laboratory tests that are commonly part of the initial evaluation include a complete blood count, sputum cultures for bacteria, mycobacteria, and fungi, testing for cystic fibrosis, and immunoglobulin levels.<ref name="auto1"/> Additional tests that are sometimes indicated include testing for specific genetic disorders.<ref name="Bronchiectasis"/>

Lung function testing is used for the assessment and monitoring of functional impairment due to bronchiectasis. These tests may include spirometry and walking tests.<ref name=":02"/> Obstructive lung impairment is the most common finding but restrictive lung impairment can be seen in advanced disease. Flexible bronchoscopy may be performed when sputum studies are negative and a focal obstructing lesion is suspected.<ref name="Kwon 302–307"/>

A chest x-ray is abnormal in most patients with bronchiectasis. Computed tomography is recommended to confirm the diagnosis and is also used to describe the distribution and grade the severity of the disease. Radiographic findings include airway dilation, bronchial wall thickening, and atelectasis.<ref name="Mc20132">Template:Cite journal</ref> There are three types bronchiectasis that can be seen on CT scan, namely cylindrical, varicose, and cystic bronchiectasis.<ref>Template:Cite journal</ref>

• Bronchiectasis (3705143327).jpg

  Bronchiectasis primarily in the middle lobe of the right lung.

• Bronchiectasis .jpg

  Bronchiectasis secondary to a large carcinoid tumor (not shown) that was completely obstructing the bronchus proximally. Dilation of the airways is present.

Prevention

In preventing bronchiectasis, it is necessary to prevent the lung infections and lung damage that can cause it.<ref name=":4" /> Children should be immunized against measles, pertussis, pneumonia, and other acute respiratory infections of childhood. Additionally, parents should stay alert to keep children from inhaling objects such as pieces of food or small toys that may get stuck in small airways.<ref name=":4" /> Smoking and other toxic fumes and gases should be avoided by all patients with bronchiectasis to decrease the development of infections (such as bronchitis) and further complications.<ref>Template:Cite journal</ref>

Treatments to slow down the progression of this chronic disease include keeping bronchial airways clear and secretions weakened through various forms of airway clearance. Aggressively treating bronchial infections with antibiotics to prevent the destructive cycle of infection, damage to bronchi and bronchioles, and more infection is also standard treatment. Regular vaccination against pneumonia, influenza, and pertussis are generally advised. A healthy body mass index and regular doctor visits may have beneficial effects on the prevention of progressing bronchiectasis. The presence of hypoxemia, hypercapnia, dyspnea level and radiographic extent can greatly affect the mortality rate from this disease.<ref>Template:Cite journal</ref>

Management

A comprehensive approach to the management of bronchiectasis is recommended.<ref name="Chalmers 1446–1462">Template:Cite journal</ref> It is important to establish whether an underlying modifiable cause, such as immunoglobulin deficiency or alpha-1 antitrypsin deficiency is present.<ref name="Chalmers 1446–1462"/> The next steps include controlling infections and bronchial secretions, relieving airway obstructions, removing affected portions of lung by surgery, and preventing complications.<ref>Template:Cite journal</ref>

Airway clearance

The goal of airway clearance therapy is to loosen secretions and interrupt the cycle of inflammation and infection.<ref>Template:Cite journal</ref> Airway clearance techniques improve difficulty breathing, cough, and help patients cough up phlegm and mucus plugs.<ref>Template:Cite journal</ref> Airway clearance usually uses an inhaled agent (hypertonic saline) with chest physiotherapy, such as high-frequency chest wall oscillation.<ref name="Mc2013" /> Many airway clearance techniques and devices exist. The choice of a technique or device is based on the frequency and tenacity of phlegm, patient comfort, cost, and the patient's ability to use the technique or device with minimal interference to their lifestyle.<ref name=":2">Template:Cite journal</ref> The active cycle of breathing technique (ACBT), which can be employed with or without a flutter device, is beneficial in treating those with bronchiectasis.<ref>Template:Cite journal</ref> Mucolytic agents such as dornase alfa are not recommended for individuals with non-CF bronchiectasis.<ref name=Mc2013/> Mannitol is a hyperosmolar agent that is thought to hydrate airway secretions, however, clinical trials with it have not demonstrated efficacy.<ref name=":2" />

Anti-inflammatories

The two most commonly used classes of anti-inflammatory therapies are macrolides and corticosteroids.<ref name=Mc2013/>

Despite also being antibiotics, macrolides exert immunomodulatory effects on the host inflammatory response without systemic suppression of the immune system.<ref name=Mc2013/> These effects include modifying mucus production, inhibition of biofilm production, and suppression of inflammatory mediators.<ref name=":02"/> Three large multicenter, randomized trials have shown reduced rates of exacerbations and improved cough and dyspnea with use of macrolide therapy.<ref name="auto1">Template:Cite journal</ref> The impact of adverse effects of macrolides such as gastrointestinal symptoms, hepatotoxicity, and increased antimicrobial resistance needs ongoing review and study.<ref name=Qi2014/>

Inhaled corticosteroid therapy can reduce sputum production and decrease airway constriction over a period of time, helping prevent progression of bronchiectasis.<ref name=":3"/> Long term use of high-dose inhaled corticosteroids can lead to adverse consequences such as cataracts and osteoporosis.<ref name=Mc2013/> It is not recommended for routine use in children.<ref name="HILL201122">Template:Cite journal</ref> One commonly used therapy is beclometasone dipropionate.<ref>Template:Cite journal</ref>

Antibiotics

File:Zithromax (Azithromycin) tablets.jpg

Azithromycin is a macrolide commonly used in bronchiectasis.

Antibiotics are used in bronchiectasis to eradicate P. aeruginosa or MRSA, to suppress the burden of chronic bacterial colonization, and to treat exacerbations.<ref name=Mc2013/> The use of daily oral non-macrolide antibiotic treatment has been studied in small case series, but not in randomized trials.<ref name="auto1"/> The role of inhaled antibiotics in non-CF bronchiectasis has recently evolved with two society guidelines and a systematic review suggesting a therapeutic trial of inhaled antibiotics in patients with three or more exacerbations per year and P. aeruginosa in their sputum.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> Options for inhaled antibiotics include aerosolized tobramycin, inhaled ciprofloxacin, aerosolized aztreonam, and aerosolized colistin.<ref name=":02" /> However, there arises a problem with inhaled antibiotic treatments, such as ciprofloxacin, of staying in the desired area of the infected lung tissues for sufficient time to provide optimal treatment.<ref name="ReferenceA">Template:Cite journal</ref> To combat this and prolong the amount of time the antibiotic spends in the lung tissue, current study trials have moved to develop inhalable nanostructured lipid carriers for the antibiotics.<ref name="ReferenceA"/>

Bronchodilators

Some clinical trials have shown a benefit with inhaled bronchodilators in certain people with bronchiectasis.<ref name=Mc2013/> In people with demonstrated bronchodilator reversibility on spirometry, the use of inhaled bronchodilators resulted in improved dyspnea, cough, and quality of life without any increase in adverse events.<ref name="Pasteur i1–58"/> However, overall there is a lack of data to recommend use of bronchodilators in all patients with bronchiectasis.<ref>Template:Cite journal</ref>

Surgery

The primary role of surgery in the management of bronchiectasis is in localized disease to remove segments of the lung or to control massive hemoptysis.<ref name=":02" /> Additionally, surgery is used to remove an airway obstruction that is contributing to bronchiectasis. The goals are conservative, aiming to control specific disease manifestations rather than cure or eliminate all areas of bronchiectasis.<ref name=":12">Template:Cite journal</ref> Surgical case series have shown low operative mortality rate (less than 2%) and improvement of symptoms in the majority of patients selected to receive surgery.<ref>Template:Cite journal</ref> However, no randomized clinical trials have been performed evaluating the efficacy of surgery in bronchiectasis.<ref name=":12" />

Clinical trials

Results from a phase 2 clinical trial were published in 2018.Template:R In a placebo-controlled, double-blind study conducted in 256 patients worldwide, patients who received Brensocatib reported prolonged time to the first exacerbation and also reduced rate of yearly exacerbation.Template:R

Prognosis

Two clinical scales have been used to predict disease severity and outcomes in bronchiectasis; the Bronchiectasis Severity Index and the FACED scale. The FACED scale uses the FEV-1 (forced expiratory volume in 1 second), age of the affected person, presence of chronic infection, extent of disease (number of lung lobes involved) and dyspnea scale rating (MRC dyspnea scale) to predict clinical outcomes in bronchiectasis. The Bronchiectasis Severity Index uses the same criteria as the FACED scale in addition to including criteria related to number of hospital admissions, annual exacerbations, colonization with other organisms and BMI (body mass index) less than 18.5. A decreased FEV-1, increasing age, presence of chronic infection (especially pseudomonas), a greater extent of lung involvement, high clinical dyspnea scale ratings, increased hospital admissions, a high number of annual exacerbations, and a BMI less than 18.5 lead to higher scores on both clinical scales and are associated with a poor prognosis in bronchiectasis; including increased mortality.<ref name="O'Donnell NEJM">Template:Cite journal</ref>

Epidemiology

The prevalence and incidence of bronchiectasis is unclear as the symptoms are variable.<ref>Template:Cite encyclopedia</ref> The disease affects between 1 per 1000 and 1 per 250,000 adults.<ref name=Cot2015/> The disease is more common in women and in the elderly.<ref name=Mc2013/> In a Medicare cohort study in the United States, consisting of adults 65 years and older, the prevalence of bronchiectasis was 701 per 100,000 persons.<ref name="Chest Henkle">Template:Cite journal</ref> A similar prevalence rate of bronchiectasis has been reported in other countries including China, Germany, the United Kingdom, Spain and Singapore.<ref name="O'Donnell NEJM" /> Those with a dual COPD and bronchiectasis diagnosis are more likely to be cigarette smokers and more likely to be hospitalized as compared to those with bronchiectasis without COPD.<ref name="Chest Henkle" /> It became less common since the 1950s, with the introduction of antibiotics.<ref name=Cot2015/> It is more common among certain ethnic groups such as indigenous people.<ref name=Cot2015/>

An estimated 350,000 to 500,000 adults have bronchiectasis in the United States.<ref name=":1">Template:Cite journal</ref> Specifically, children of the indigenous populations of Australia, Alaska, Canada and New Zealand have significantly higher rates than other populations.<ref name=":5">Template:Cite journal</ref> Overall, a shortage of data exists concerning the epidemiology of bronchiectasis in Asia, Africa, and South America.<ref name=":5" />

The prevalence and incidence of bronchiectasis has increased greatly in the 21st century. In a Medicare cohort analysis, consisting of adults 65 years and older in the United States; the annual rates of diagnosis have increased by 8.7% every year between 2000 and 2007.<ref name=Mc2013/><ref name="Seitz Chest">Template:Cite journal</ref> This large increase in the diagnosis of bronchiectasis may be due to increased recognition of the disease (including more widespread use of CT scans) or it may be due to an increase in the underlying causes of bronchiectasis.<ref name="O'Donnell NEJM" />

History

René Laennec, the man who invented the stethoscope, used his invention to first discover bronchiectasis in 1819.<ref>Template:Cite journal</ref>

The disease was researched in greater detail by Sir William Osler, one of the four founding professors of Johns Hopkins Hospital, in the late 1800s. It is suspected that Osler himself died of complications from undiagnosed bronchiectasis. His biographies mention that he had frequent severe chest infections for many years.<ref>Template:Cite journal</ref>

The term "bronchiectasis" comes from the Greek words bronkhia (meaning "airway") and ektasis (meaning "widening").<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Society and culture

Judith Durham of the Australian band The Seekers died of bronchiectasis on August 5, 2022, at the age of 79.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>